Money terms

Every money term the lessons define, in one place. Plain language, no jargon for its own sake — and each definition links straight to the lesson that teaches it.

321 terms across the curriculum. Back to the lessons · Search lessons · Study as flashcards.

A

Above-the-line deduction: a deduction subtracted from gross income before the standard deduction. Half of self-employment tax qualifies, partially — never fully — offsetting the extra FICA burden. — in Gig Work & 1099s: The Self-Employment Tax Surprise
Accumulation phase: the years you're adding money to your investments. Here, a crash early is an advantage. — in Sequence of Returns: Why a Crash Hurts More at the Finish Line
Active fund: a fund run by a manager trying to beat the market, charging a higher fee for the attempt. Most fail to beat a cheap index fund after fees. — in Index Funds, ETFs & the Quiet Cost of Fees
Advisor / wrap fee: a charge for managing your money, usually a percentage of your entire balance per year (often ~1%). Levied on the whole pot, including its growth. — in Fees Everywhere: The Costs That Stack
All-in fee: the sum of every annual cost of investing: fund expense ratios, advisory fees, and trading/spread costs combined. The single number you should judge a portfolio's cost by. — in Fees Everywhere: The Costs That Stack
Amortization: paying a loan off in fixed installments where each payment's interest/principal mix shifts as the balance falls. — in Loans & Amortization
Amortized / financed: paying off a shortfall over time through a loan or card instead of cash, which adds interest a sinking fund never does. — in Sinking Funds: Saving Monthly for the Bill You Know Is Coming
Annuitize: to irrevocably exchange a lump sum for the income stream, giving up access to the principal. — in Annuities: Buying Yourself a Paycheck for Life
Annuity: a stream of equal payments over time. "Ordinary" pays at the end of each period; "due" pays at the start, and is worth (1 + r)× more. — in Present Value: Should You Take the Lump Sum or the Payments? , Annuities: Buying Yourself a Paycheck for Life
Appreciating asset: something that tends to rise in value over time (a home, a productive business, a marketable skill). — in Good Debt vs Bad Debt: It's Not the Loan, It's What You Bought
Appreciation: the rise in the property's market value over time. — in Real-Estate Investing: Cap Rate, Cash Flow, and the Magic (and Menace) of Leverage
APR: the card's yearly interest rate; divide by 12 for the monthly rate your balance is actually charged. — in Credit Cards & the Minimum-Payment Trap
APR (annual percentage rate): the nominal yearly rate: the per-period rate multiplied by the number of periods, ignoring compounding. — in Interest, APR & APY , Buy Now, Pay Later — or Save Up First? The True Cost of Financing a Purchase
APR reversion (the "go-to" rate): the normal ongoing interest rate a promotional balance reverts to once the intro window ends, applied to however much is still outstanding. — in Balance Transfer: The 0%-APR Card That Becomes a Trap If You Miss the Deadline
APY (annual percentage yield): the effective yearly rate: what a balance actually grows or costs over a year once compounding is included. Also called effective annual rate (EAR). — in Interest, APR & APY
Arithmetic mean return: the simple average of the yearly returns (add them, divide). The number usually quoted; it overstates what you actually compound at whenever returns vary. — in Why a 50% Loss Needs a 100% Gain: Volatility Drag
Asset: anything you own that has value: cash, investments, home equity, a paid-off car. — in Net Worth & the Order of Operations: Where Every Dollar Goes First
Asset allocation: how you split your money across broad asset classes (chiefly stocks vs bonds); the decision that drives most of a portfolio's risk and return. — in Asset Allocation: How Much in Stocks vs Bonds?
Asset location: choosing which account holds each investment to minimize taxes: high-turnover strategies in sheltered accounts, buy-and-hold in taxable ones. — in Capital Gains: Why Holding On (and Trading Less) Beats the Tax
Auto-escalation: a retirement-plan feature that automatically raises your contribution rate each year, a built-in defense against creep that captures raises for you. — in Lifestyle Creep: Bank Your Raises or Spend Them?
Avalanche: paying minimums on everything, with every extra dollar to the highest-rate debt. Minimizes total interest paid. — in Debt Payoff Strategies: Avalanche vs Snowball , Debt Consolidation: Does Trading Several Debts for One Actually Help?
Average cost: the average price you actually paid per share: total invested ÷ shares owned. Averaging in pushes it below the market's average price. — in Dollar-Cost Averaging: Investing Through the Ups and Downs

B

Bad debt: borrowing for an asset that loses value, or grows slower than the loan costs. You pay interest and lose value, the two compounding against you. — in Good Debt vs Bad Debt: It's Not the Loan, It's What You Bought
Balance due (bill): what you owe in April because you withheld less than your tax. Fine if planned for; penalized if you under-withhold too far. — in Paycheck Withholding & the Tax-Refund Myth
Balance transfer: moving debt from one card to another, usually to capture a promotional interest rate on the new card. — in Balance Transfer: The 0%-APR Card That Becomes a Trap If You Miss the Deadline
Balance-transfer fee: an upfront charge, typically 3–5% of the amount moved, added to the new card's balance at the time of transfer. — in Balance Transfer: The 0%-APR Card That Becomes a Trap If You Miss the Deadline
Benefit cap: the hard monthly maximum the policy pays regardless of income; where it binds, the effective replacement rate falls below the label. — in Disability Insurance: Insuring Your Paycheck, Not Just Your Stuff
Benefits cliff: an income threshold where a benefit cuts off all at once, so a small raise can cost more than it pays and leave a family with less. — in The Benefits Cliff: When a Raise Leaves You Worse Off
Blended rate: the effective average rate across several debts, weighted by their balances; the number a consolidation offer needs to beat. — in Debt Consolidation: Does Trading Several Debts for One Actually Help?
BNPL (Buy Now, Pay Later): splitting a purchase into installments, often "interest-free" up front but with steep late fees and deferred-interest traps in the fine print. — in Buy Now, Pay Later — or Save Up First? The True Cost of Financing a Purchase
Bond: a loan you make to a government or company: you pay the price, collect fixed coupons, and get the face value back at maturity. — in Bonds: Why Their Prices Move Backwards
Break-even: the point in time when accumulated savings finally equal the up-front cost. Before it you've lost money; after it you're ahead. The central number in every buy-down decision. — in Mortgage Points: Buying Down Your Rate Is a Break-Even , Options: Calls, Puts, and the Hockey-Stick Payoff
Break-even (years to break even): how long you must stay in a home before owning's net worth passes renting-and-investing's. The central number in the whole decision. — in Rent vs Buy: It's a Break-Even, Not a Battle
Break-even month: closing costs ÷ monthly payment saving: the month the refinance has paid for itself. Keep the loan past it to come out ahead. — in Refinancing a Loan: When Does It Actually Pay Off?
Break-even rate: the discount rate at which a lump sum and a payment stream are worth exactly the same today; equivalently, the implied return the payments pay on the cash you'd give up. — in Present Value: Should You Take the Lump Sum or the Payments?
Break-even return: the nominal return that exactly matches inflation, leaving a real return of zero. Earn less and you lose purchasing power; earn more and you gain it. — in Real Returns: What Your Money Is Actually Earning
Break-even spending: the annual medical-spending level where both plans cost exactly the same; the single number that decides which plan is actually cheaper for you. — in HDHP + HSA vs PPO: Picking a Health Plan Without Guessing
Building equity: the share of the home you actually own: its value minus what you still owe. Grows as you pay down principal and as the home appreciates. — in Rent vs Buy: It's a Break-Even, Not a Battle
Buy term and invest the difference (BTID): buy cheap term and invest the premium you saved versus whole life; the side fund usually dwarfs the policy's cash value. — in Insurance: Buy Term and Invest the Difference
Buying down the rate: paying up front (via points) for a lower interest rate, and so a smaller payment and less lifetime interest. — in Mortgage Points: Buying Down Your Rate Is a Break-Even

C

Call / put: the right to buy / to sell the stock at the strike price. — in Options: Calls, Puts, and the Hockey-Stick Payoff
Cap rate: net operating income ÷ price. The property's yield ignoring financing; the standard way to compare buildings. — in Real-Estate Investing: Cap Rate, Cash Flow, and the Magic (and Menace) of Leverage
Capital appreciation: the gain from a stock's price rising above what you paid. Only realized when you sell, and it can reverse. — in Stocks: Price, Dividends & What 'Total Return' Really Means
Capital gain: the profit when you sell an investment for more than you paid; taxed only when realized (sold). — in Capital Gains: Why Holding On (and Trading Less) Beats the Tax
Capital loss / gain: the loss or profit from selling an investment; losses offset gains first. — in Tax-Loss Harvesting: Turning a Loser Into a Tax Break
Carry-forward: unused losses applied to future tax years, with no expiration. — in Tax-Loss Harvesting: Turning a Loser Into a Tax Break
Cash discount / surcharge: the price edge a cash (or debit) buyer gets that a financed buyer forfeits. Functionally an extra interest cost on the financed purchase. — in Buy Now, Pay Later — or Save Up First? The True Cost of Financing a Purchase
Cash flow: money in versus money out over a period. Positive cash flow (a surplus) is what you save; negative cash flow (a deficit) is what becomes debt. — in Budgeting & Cash Flow
Cash value: the savings balance inside a whole-life policy, credited at the insurer's low rate and locked behind surrender charges. — in Insurance: Buy Term and Invest the Difference
Cash-on-cash return: first-year cash flow ÷ the cash you invested. What your real money earns in spendable income; can be negative. — in Real-Estate Investing: Cap Rate, Cash Flow, and the Magic (and Menace) of Leverage
Catch-up contribution: the larger monthly amount a late starter needs to match an early one over a shorter remaining runway; it climbs steeply, and past a point no amount suffices. — in The Cost of Waiting: Why a Late Start Costs More Than the Years You Skip
Certificate of deposit (CD): a deposit locked for a fixed term at a fixed rate; cashing out early triggers an early-withdrawal penalty. — in Bank Accounts: Where Your Cash Should Actually Sit
Closing costs: the one-time fees to buy (lender, title, inspection, taxes), typically a few percent of the price. Sunk cash the moment you buy. — in Rent vs Buy: It's a Break-Even, Not a Battle , Mortgage Points: Buying Down Your Rate Is a Break-Even , Refinancing a Loan: When Does It Actually Pay Off?
Coast FIRE: the point at which your invested pile is large enough that compound growth alone will reach your retirement number by your target date, with no further contributions required. — in Coast FIRE: The Age You Can Stop Saving and Still Retire On Time
Coast number: the pile you'd need at a given age so that growth alone hits your target by retirement; it's your number discounted back through compounding, and it rises with age toward the full number. — in Coast FIRE: The Age You Can Stop Saving and Still Retire On Time
Coasting: continuing to work for living expenses while no longer contributing to retirement, because growth is already carrying the pile to the finish. — in Coast FIRE: The Age You Can Stop Saving and Still Retire On Time
Coinsurance: a percentage share of costs you keep paying between the deductible and the true out-of-pocket max, simplified away in this lesson's model. — in HDHP + HSA vs PPO: Picking a Health Plan Without Guessing
Combined loan-to-value (CLTV): your first mortgage plus the HELOC, divided by your home's value; lenders typically cap it around 80%. — in HELOC: Borrowing Against Your Home
Compounding frequency: how often interest is added to the balance (n in the formula). More frequent means a higher APY for the same APR, with sharply diminishing returns. — in Interest, APR & APY
Compounding gap: a percentage difference between two growing numbers that translates into a growing (not constant) DOLLAR difference over time, because a fixed percentage of a larger base is itself larger. — in The Cost of Never Negotiating: A Small Raise, Compounded Over a Career
Compounding period: how often interest is added back (here, monthly). — in Compound Interest & the Time Value of Money
Continuous compounding: the limit of compounding infinitely often: APY = e^APR − 1. The ceiling no real account quite reaches, and daily compounding nearly touches. — in Interest, APR & APY
Correlation: how strongly two assets tend to move in the same direction at the same time, from +1 (perfect lockstep) through 0 (independent) to −1 (perfect opposites). The lower it is, the bigger the diversification benefit. — in Diversification: The Closest Thing to a Free Lunch
Cosigner: someone who signs a loan alongside the primary borrower and becomes equally, fully liable for the entire balance — not a partial guarantee, not contingent on default. — in Co-Signing a Loan: Vouching for Someone Else's Debt
Cosigner release: a feature some loans offer to remove the cosigner after the primary borrower builds a track record of on-time payments — not automatic, and not offered by every lender. — in Co-Signing a Loan: Vouching for Someone Else's Debt
Cost basis: what you paid for an investment; your gain or loss is measured from it. — in Tax-Loss Harvesting: Turning a Loser Into a Tax Break , Capital Gains: Why Holding On (and Trading Less) Beats the Tax
Cost of waiting: the future wealth given up by delaying the start of investing; far larger than the contributions skipped, because the skipped years are the longest-compounding ones. — in The Cost of Waiting: Why a Late Start Costs More Than the Years You Skip
Cost-of-living index: a number (national average = 100) for how expensive a place is. Dividing your pay by it converts dollars into comparable purchasing power. — in Two Job Offers: Compare Total Comp, Not Salary
Coupon / coupon rate: the fixed interest a bond pays, as an annual percentage of its face value. A $1,000 bond with a 5% coupon pays $50 a year, locked in for life. — in Bonds: Why Their Prices Move Backwards
Credit mix: the variety of credit types you manage. A small factor (10%). — in Credit Scores: What Actually Moves the Number
Credit score: a 300–850 number summarizing how reliably you repay debt, used to decide approval and pricing. — in Credit Scores: What Actually Moves the Number
Credit utilization: the share of your available credit you're using (balances ÷ limits). Lower is better; it's the fastest factor to move. — in Credit Scores: What Actually Moves the Number
Cushion / starter emergency fund: a small amount of cash set aside specifically to absorb a surprise expense without borrowing for it. — in Emergency Fund or Pay Off Debt First?

D

Death benefit: the payout a life-insurance policy makes if you die while covered. — in Insurance: Buy Term and Invest the Difference
Debt consolidation: paying off several existing debts with one new loan, usually at a single blended rate, so you make one payment instead of several. — in Debt Consolidation: Does Trading Several Debts for One Actually Help?
Debt-free date: the month the last balance hits zero; what both strategies are actually racing toward. — in Debt Payoff Strategies: Avalanche vs Snowball
Debt-to-income ratio (DTI): monthly debt payments divided by gross monthly income; lenders use it to decide how much more you can qualify to borrow. A cosigned loan's payment counts in full, immediately. — in Co-Signing a Loan: Vouching for Someone Else's Debt
Decumulation (drawdown) phase: the years you're withdrawing money. Here, the risk reverses: a crash at the start is the danger. — in Sequence of Returns: Why a Crash Hurts More at the Finish Line
Deductible: the part of a claim you pay yourself before coverage starts. A higher deductible means a lower premium — you've agreed to self-fund the small losses. — in Insurance: Buy Term and Invest the Difference , HDHP + HSA vs PPO: Picking a Health Plan Without Guessing
Deemed default / delinquency: when a payment is missed; it reports to every party liable for the account, cosigner included, regardless of who was supposed to make the payment. — in Co-Signing a Loan: Vouching for Someone Else's Debt
Deemed distribution: an unpaid loan balance treated as if you withdrew it: taxed as ordinary income, plus a 10% penalty if you're under 59½. — in Borrowing From Your Own 401(k): The Loan That Sounds Free
Deferred interest: a "0% promo" that charges all the back-interest, on the whole original balance, if any amount is left when the promo ends. The most common way a "free" loan turns costly. — in Buy Now, Pay Later — or Save Up First? The True Cost of Financing a Purchase
Depreciating asset: something that loses value over time (a car, electronics, anything consumed). — in Good Debt vs Bad Debt: It's Not the Loan, It's What You Bought
Depreciation: the value an asset loses over time. For a car it's usually the largest cost of ownership, and it's steepest in the first few years. — in Buying a Car: New vs Used vs Lease
Depreciation cliff: the rapid early drop in a new car's value (~20% in year one), absorbed by whoever owns the car when it's new. — in Buying a Car: New vs Used vs Lease
Discount factor: the multiplier 1 / (1 + r)^t that converts a dollar t years out into today's dollars. Smaller the further out the payment and the higher the rate. — in Present Value: Should You Take the Lump Sum or the Payments?
Discount point: cash paid at closing, conventionally 1% of the loan, to buy your interest rate down. The classic "pay now to save later" trade. — in Mortgage Points: Buying Down Your Rate Is a Break-Even
Discount rate: the annual return you could earn on money, used to shrink future dollars back to today. The single most important input; it is your opportunity cost. — in Present Value: Should You Take the Lump Sum or the Payments?
Discretionary income: income above a protected floor (roughly 150% of the poverty line). The income-driven payment is a percentage of this, not of your whole paycheck. — in Student Loans: Standard vs Income-Driven Repayment (and Forgiveness)
Diversification: spreading money across assets whose returns don't move in lockstep, so their asset-specific ups and downs partly cancel and the blend's range of outcomes narrows without lowering its expected return. — in Diversification: The Closest Thing to a Free Lunch
Dividend: cash a company pays its shareholders out of profits, typically a few times a year. Not all companies pay one. — in Stocks: Price, Dividends & What 'Total Return' Really Means
Dividend reinvestment (DRIP): automatically using each dividend to buy more shares, so the payouts compound instead of sitting as cash. The source of much of the market's long-run return. — in Stocks: Price, Dividends & What 'Total Return' Really Means
Dividend yield: a stock's annual dividend as a percentage of its price (a $100 stock paying $2/year yields 2%). — in Stocks: Price, Dividends & What 'Total Return' Really Means
Dollar-cost averaging (DCA): investing a fixed dollar amount on a regular schedule, regardless of price. Buys more shares when cheap, fewer when expensive. — in Dollar-Cost Averaging: Investing Through the Ups and Downs
Dollar-weighted vs. time-weighted return: the market's time-weighted return ignores your cash flows; your dollar-weighted return reflects when you actually added or removed money. The gap between them is sequence risk in a number. — in Sequence of Returns: Why a Crash Hurts More at the Finish Line
Double taxation (on the interest): the interest you repay is after-tax money going into a pre-tax account, so that specific slice gets taxed twice: once now, once on withdrawal. — in Borrowing From Your Own 401(k): The Loan That Sounds Free
Doubling: one multiply-by-two. Counting how many doublings fit in your horizon turns exponential growth into simple, repeatable arithmetic (N doublings → 2ᴺ×). — in The Rule of 72: How Fast Does Money Double?
Doubling time: the number of years it takes a balance to grow to twice its size at a fixed rate. Exactly ln2 ÷ ln(1 + rate); approximately 72 ÷ rate%. — in The Rule of 72: How Fast Does Money Double?
Draw period: the years of interest-only payments; the balance doesn't fall on its own. — in HELOC: Borrowing Against Your Home
Drawdown: a peak-to-trough drop in value along the way. The "worst dip" is what tests whether you can actually hold an asset through a bad stretch. — in Risk & Return: Volatility Is the Price of Growth
DTI (debt-to-income ratio): your monthly debt payments divided by gross monthly income. The front-end ratio counts only housing; the back-end ratio counts all debt. — in How Much House Can You Actually Afford? The 28/36 Rule
Due diligence: verifying independently (registration, custody, audited results, how the return is actually generated) before handing over money. — in Scams & Fraud: Spotting a Too-Good-to-Be-True Return
Duration: how sensitive a bond's price is to interest-rate changes. Longer maturities (and lower coupons) have more duration and swing harder; a duration of 8 ≈ an 8% price move per 1-point rate change. — in Bonds: Why Their Prices Move Backwards

E

Early-withdrawal penalty: the interest a bank claws back if you break a CD before it matures, often a few months' worth — enough to erase the CD's advantage, or your gains. — in Bank Accounts: Where Your Cash Should Actually Sit
Earned Income Tax Credit (EITC): a large refundable credit for low-to-moderate-income workers that phases in (subsidizing early dollars), plateaus, then phases out as income rises. — in The Benefits Cliff: When a Raise Leaves You Worse Off
Effective hourly wage (after everything): a second income's real, all-in contribution — after tax, payroll tax, and its own costs — divided across a standard full-time schedule. Often far below the headline hourly rate the salary implies. — in Is a Second Income Worth It? The Childcare-and-Commute Math
Effective marginal rate: the share of your next dollar of pay you don't keep, once taxes and benefit losses are counted. Above 100% it's a losing raise; below 0% the raise is subsidized. — in The Benefits Cliff: When a Raise Leaves You Worse Off
Effective rate: total tax ÷ total income; the rate you actually pay overall (always below your marginal rate). — in Income & Take-Home Pay
Effective vs. dialed-in withholding: your withholding is "dialed in" when it lands close to the tax you actually owe, so your refund (or bill) is near zero. — in Paycheck Withholding & the Tax-Refund Myth
Efficient frontier: the curve of best-available portfolios in risk/return space; for two assets it's the trade-off curve this simulator draws. — in Asset Allocation: How Much in Stocks vs Bonds?
Elimination period: the waiting period between the disabling event and the first benefit check, typically 90–180 days on long-term policies. — in Disability Insurance: Insuring Your Paycheck, Not Just Your Stuff
Emergency fund: cash reserved for events that threaten your essentials, not for planned or optional spending. — in The Emergency Fund , Net Worth & the Order of Operations: Where Every Dollar Goes First
Employer 401(k) match: money your employer adds to your retirement account when you contribute, commonly a percentage of salary. Free money if you capture it. See Retirement Accounts & the Employer Match. — in Two Job Offers: Compare Total Comp, Not Salary
Employer match: free money your employer adds to your 401(k) when you contribute; an instant, risk-free return. — in Net Worth & the Order of Operations: Where Every Dollar Goes First , Retirement Accounts & the Employer Match: The Closest Thing to Free Money , Pay Down Debt or Invest? The Guaranteed-Return Crossover
Essentials: the monthly cost of keeping your life running: housing, food, utilities, transport, insurance, minimum debt payments. — in The Emergency Fund
ETF (exchange-traded fund): a fund (often an index fund) that trades on an exchange like a stock throughout the day. For a long-term holder it behaves like an index fund. — in Index Funds, ETFs & the Quiet Cost of Fees
Expected return: the average outcome across many possible futures: the center of the cone, not a guarantee for any single run. — in Risk & Return: Volatility Is the Price of Growth , Pay Down Debt or Invest? The Guaranteed-Return Crossover
Expense ratio: a fund's annual fee as a percentage of your balance. Charged every year, up or down. The single most important number when comparing funds. — in Index Funds, ETFs & the Quiet Cost of Fees , Fees Everywhere: The Costs That Stack
Exposure: the stretch of time a strategy carries no savings to absorb a shock. Zero cushion doesn't mean "risky" in the abstract; it means a real cost lands as new debt if anything goes wrong during that window. — in Emergency Fund or Pay Off Debt First?
Extra principal payment: money paid beyond the required payment, applied straight to the balance; it removes the schedule's last, most expensive months. — in Loans & Amortization

F

Face value (par): the amount repaid at maturity, and the base the coupon is figured on; typically $1,000. A bond trades at par only when the market rate equals its coupon. — in Bonds: Why Their Prices Move Backwards
FDIC insurance: the federal guarantee (up to a legal limit per bank) that protects your deposits even if the bank fails. It covers HYSAs and CDs at insured banks just as it covers checking. — in Bank Accounts: Where Your Cash Should Actually Sit
Fee drag: the cumulative wealth a fee removes over time. Far larger than the headline percentage, because the fee — and the growth it costs you — compounds for as long as you invest. — in Index Funds, ETFs & the Quiet Cost of Fees , Fees Everywhere: The Costs That Stack
FI number: the nest egg that makes you financially independent, roughly 25× your annual spending. Cutting spending lowers it; earning more does not. — in Which Dollar Is Worth Most: A Raise, a Side Hustle, or Cutting Costs?
FI number / your number: the nest egg that funds your retirement, usually your annual spending times twenty-five (the 4% rule). The target the coast number is chasing. — in Coast FIRE: The Age You Can Stop Saving and Still Retire On Time
FICA: the payroll tax funding Social Security (6.2%) and Medicare (1.45%). Employees pay one half; their employer pays the other. — in Which Dollar Is Worth Most: A Raise, a Side Hustle, or Cutting Costs? , Gig Work & 1099s: The Self-Employment Tax Surprise
FICA / payroll tax: Social Security (6.2%, up to a wage cap) plus Medicare (1.45%, no cap), withheld from the first dollar. — in Income & Take-Home Pay
Financial independence (FI): the point where your investments can cover your spending indefinitely, making paid work optional. — in Savings Rate: The Shockingly Simple Math of Early Retirement
Financial independence (FI) number: the amount you need invested to live off your portfolio, roughly 25× your annual spending (the 4% rule). Because it scales with spending, permanent lifestyle inflation raises this target by about 25× every extra dollar. — in Lifestyle Creep: Bank Your Raises or Spend Them?
Financial order of operations: the priority order for each new dollar: starter fund → employer match → high-interest debt → full emergency fund → tax-advantaged investing → taxable investing. — in Net Worth & the Order of Operations: Where Every Dollar Goes First
Fixed vs variable costs: fixed costs (rent) are the same each month; variable costs (groceries, fun) flex. Variable costs are where a budget has room to breathe. — in Budgeting & Cash Flow
Fixed-payment payoff: paying a constant amount each month so the principal share of every payment grows as the balance falls — amortization working for you again. — in Credit Cards & the Minimum-Payment Trap
Forgiveness: cancellation of the remaining balance at the end of an income-driven plan's term. Outside PSLF it can be taxed as income — the "tax bomb." — in Student Loans: Standard vs Income-Driven Repayment (and Forgiveness)
Front-end / back-end ratio: the 28% (housing-only) and 36% (all-debt) DTI caps lenders size loans against. — in How Much House Can You Actually Afford? The 28/36 Rule
FSA (Flexible Spending Account): a different account that sounds similar but is typically use-it-or-lose-it each year, unlike the HSA's permanent, rolling balance. — in The HSA: The Only Account With a Triple Tax Advantage
Fully-indexed rate: the rate the loan resets toward: a market index plus the lender's fixed margin. Where the rate is headed once the teaser ends. — in Adjustable-Rate Mortgages: The Teaser That Resets

G

Gap multiple: the lifetime earnings gap expressed as a multiple of the one-time starting gap; how many times over a single successful negotiation repaid itself. — in The Cost of Never Negotiating: A Small Raise, Compounded Over a Career
Geometric mean return (CAGR): the single steady rate that turns your real starting balance into your real ending balance. Always ≤ the arithmetic mean, equal only when every year is identical. — in Why a 50% Loss Needs a 100% Gain: Volatility Drag
Glide path: a strategy that gradually shifts a portfolio from growth assets toward safer ones as retirement approaches, precisely to blunt sequence risk near the transition. — in Sequence of Returns: Why a Crash Hurts More at the Finish Line , Asset Allocation: How Much in Stocks vs Bonds?
Good debt: borrowing where the asset you bought grows in value (or earning power) faster than the loan's interest rate, so the debt pays for itself. Defined by the asset, not the loan. — in Good Debt vs Bad Debt: It's Not the Loan, It's What You Bought
Gross pay: your salary before any taxes or deductions. — in Income & Take-Home Pay
Gross-up: an employer arrangement that adds the premium to your taxable wages so the benefit itself becomes tax-free. — in Disability Insurance: Insuring Your Paycheck, Not Just Your Stuff
Guaranteed return: the return you earn with certainty by paying down debt, exactly equal to that debt's interest rate. See pay down debt or invest. — in Emergency Fund or Pay Off Debt First? , You Just Got a Windfall: Where Should It Go? , Pay Down Debt or Invest? The Guaranteed-Return Crossover

H

Hard inquiry: the check a lender runs when you apply; a cluster of them is the "new credit" factor working against you. — in Credit Scores: What Actually Moves the Number
HDHP (High-Deductible Health Plan): the insurance you must be enrolled in to contribute to an HSA; lower premiums, a higher deductible. — in The HSA: The Only Account With a Triple Tax Advantage , HDHP + HSA vs PPO: Picking a Health Plan Without Guessing
Head start: the advantage of earlier dollars having more time to grow; large enough that fewer early dollars can beat more later ones. — in The Cost of Waiting: Why a Late Start Costs More Than the Years You Skip
HELOC (home equity line of credit): a revolving credit line secured by your home, with a draw period and a repayment period. — in HELOC: Borrowing Against Your Home
High-interest debt: debt (typically credit cards) whose rate is high enough — often 20%+ — that paying it off beats any reliable investment return. — in Net Worth & the Order of Operations: Where Every Dollar Goes First
High-yield investment program (HYIP): an online scam promising fixed, above-market daily or weekly returns; almost always a Ponzi. — in Scams & Fraud: Spotting a Too-Good-to-Be-True Return
High-yield savings account (HYSA): a savings account paying meaningfully more interest than a standard one; the usual home for an emergency fund. — in The Emergency Fund , Bank Accounts: Where Your Cash Should Actually Sit
Home equity: your home's value minus what you still owe against it; the ceiling on how much a HELOC can ever lend you. — in HELOC: Borrowing Against Your Home
House poor: able to make the mortgage payment but with little left over for everything else, the result of stretching to the top of the lender's ceiling. — in How Much House Can You Actually Afford? The 28/36 Rule
HSA (Health Savings Account): a tax-advantaged account, available to those on a high-deductible health plan, whose contributions, growth, and qualified medical withdrawals are all tax-free. — in The HSA: The Only Account With a Triple Tax Advantage , HDHP + HSA vs PPO: Picking a Health Plan Without Guessing

I

In / out of the money: whether exercising now would have value (in) or not (out). — in Options: Calls, Puts, and the Hockey-Stick Payoff
Income-driven repayment (IDR): a plan that caps your payment at a share of discretionary income and forgives the remaining balance after 20–25 years (10 under PSLF). — in Student Loans: Standard vs Income-Driven Repayment (and Forgiveness)
Index fund: a fund that holds every company in a market index in proportion, giving you the whole market's return in one cheap, diversified package instead of picking stocks. — in Index Funds, ETFs & the Quiet Cost of Fees
Inflation: the rate at which prices rise (so each dollar buys a little less). — in What Is Money & Inflation , Real Returns: What Your Money Is Actually Earning
Interest: the rent on borrowed money: balance × the monthly rate, every month. — in Loans & Amortization
Intrinsic value: how far the option is in the money right now. — in Options: Calls, Puts, and the Hockey-Stick Payoff
IRA: an Individual Retirement Account you open yourself, with the same traditional/Roth choice. — in Retirement Accounts & the Employer Match: The Closest Thing to Free Money

L

Latte factor: the popularized name for the compounded long-run cost of a small, recurring expense; a concrete application of opportunity cost. — in The Latte Factor: What a Small Daily Habit Really Costs
Lease: paying to use a car for a set term (covering its depreciation during that time plus a finance charge) and returning it at the end, with no ownership or equity. — in Buying a Car: New vs Used vs Lease
Leverage: using borrowed money to control a larger asset. It magnifies the asset's return in both directions: a friend when the asset grows, an enemy when it shrinks. — in Good Debt vs Bad Debt: It's Not the Loan, It's What You Bought , Real-Estate Investing: Cap Rate, Cash Flow, and the Magic (and Menace) of Leverage
Liability: anything you owe: credit-card balances, student loans, a mortgage, a car loan. — in Net Worth & the Order of Operations: Where Every Dollar Goes First
Lifestyle creep: the tendency for spending to rise to meet a rising income, keeping the savings rate flat so raises don't shorten the road to FI. — in Savings Rate: The Shockingly Simple Math of Early Retirement
Lifestyle creep (lifestyle inflation): the tendency for spending to rise alongside income, so raises get absorbed into a fancier life instead of savings. The default outcome unless you act. — in Lifestyle Creep: Bank Your Raises or Spend Them?
Lifetime earnings gap: every year's dollar difference between two salary paths, added up over a whole career. Always larger than the starting gap times the years, whenever raises are nonzero. — in The Cost of Never Negotiating: A Small Raise, Compounded Over a Career
Liquidity: how quickly money can be spent at full value. An emergency fund trades return for maximum liquidity. — in The Emergency Fund , Bank Accounts: Where Your Cash Should Actually Sit
Long / short: you bought the option (long) / you sold or wrote it (short). — in Options: Calls, Puts, and the Hockey-Stick Payoff
Long-term capital-gains rate: the (usually lower) rate owed on investment growth held over a year in a taxable account — what a cashed-out-and-reinvested balance pays instead of ordinary income tax, and only on its growth, not its principal. — in Cashing Out a 401(k) When You Leave a Job — vs. Rolling It Over
Long-term disability (LTD): insurance replacing a fraction of income when illness or injury stops you from working for months or years; the employer-sponsored kind is "group" coverage. — in Disability Insurance: Insuring Your Paycheck, Not Just Your Stuff
Long-term gain: a gain on an asset held more than a year, taxed at the lower 0/15/20% rate. — in Capital Gains: Why Holding On (and Trading Less) Beats the Tax
Longevity risk: the risk of outliving your savings; the risk an annuity is designed to remove. — in Annuities: Buying Yourself a Paycheck for Life
Loss aversion: the tendency to feel losses about twice as intensely as equivalent gains. The emotional engine behind panic-selling. — in Behavioral Finance: Why We Sell at the Bottom
Lump-sum investing: putting the entire available amount in at once, getting full market exposure immediately. — in Dollar-Cost Averaging: Investing Through the Ups and Downs

M

Marginal rate: the rate on your next dollar earned (your top bracket). — in Income & Take-Home Pay
Marginal stacking: in a joint tax return, a second earner's income is taxed starting at the bracket the first earner's income already reached, not from the bottom bracket up. — in Is a Second Income Worth It? The Childcare-and-Commute Math
Marginal tax rate: the rate on your next dollar of income (your top bracket). What a raise or side-hustle dollar is actually taxed at — always higher than your overall effective rate. See Income & Take-Home Pay. — in Which Dollar Is Worth Most: A Raise, a Side Hustle, or Cutting Costs? , Roth vs. Traditional: Pay the Tax Now, or Later? , Two Job Offers: Compare Total Comp, Not Salary
Market (systematic) risk: the risk that hits all assets at once and can't be diversified away. It's the part you're paid the risk premium to bear. — in Diversification: The Closest Thing to a Free Lunch
Maturity: the date the bond repays its face value and ends. Bonds range from months to 30+ years. — in Bonds: Why Their Prices Move Backwards
Means-tested benefit: a benefit available only below an income limit (Medicaid, SNAP, ACA subsidies, childcare assistance). The limit is what creates the cliff. — in The Benefits Cliff: When a Raise Leaves You Worse Off
Minimum payment: the smallest payment that keeps the account in good standing; usually a percent of the balance with a small dollar floor. — in Credit Cards & the Minimum-Payment Trap
Minimum-variance mix: the single lowest-risk portfolio you can build from the available assets. Because of diversification it usually holds some of the risky asset, not zero. — in Asset Allocation: How Much in Stocks vs Bonds?
Missing the best days: the finding that a tiny number of the market's strongest days drive a huge share of long-run returns, so being out of the market briefly can devastate your results. — in Behavioral Finance: Why We Sell at the Bottom
Mortality credits: the extra return survivors earn because early-dying members of the pool forfeit their premiums; what lets an annuity out-pay a bond. — in Annuities: Buying Yourself a Paycheck for Life

N

Negative amortization: see credit cards for what happens when a payment can't even keep up with a balance's interest. — in Emergency Fund or Pay Off Debt First? , Student Loans: Standard vs Income-Driven Repayment (and Forgiveness)
Net contribution: what a second income actually adds to a household's finances: take-home pay minus the costs that exist only because the job does. Can be negative. — in Is a Second Income Worth It? The Childcare-and-Commute Math
Net resources: take-home pay plus every benefit and refundable credit a household qualifies for. The right number to judge an income decision by; salary and even take-home can mislead. — in The Benefits Cliff: When a Raise Leaves You Worse Off
Net worth: everything you own minus everything you owe; the single number that tracks financial progress. — in Net Worth & the Order of Operations: Where Every Dollar Goes First
NOI (Net Operating Income): annual rent minus operating expenses, excluding the mortgage. — in Real-Estate Investing: Cap Rate, Cash Flow, and the Magic (and Menace) of Leverage
Nominal return: the headline rate on the statement, before inflation. What the balance literally grows by. — in Real Returns: What Your Money Is Actually Earning
Nominal value: the face number, before adjusting for inflation. — in What Is Money & Inflation

O

Opportunity cost: the value of the best alternative you give up when you choose. — in Opportunity Cost & Trade-Offs , Buy Now, Pay Later — or Save Up First? The True Cost of Financing a Purchase , Borrowing From Your Own 401(k): The Loan That Sounds Free , You Just Got a Windfall: Where Should It Go? , Rent vs Buy: It's a Break-Even, Not a Battle
Order of operations: the priority list for a new dollar: emergency fund and free employer match, then high-interest debt, then investing, with cash as the short-term waiting room. — in You Just Got a Windfall: Where Should It Go? , Pay Down Debt or Invest? The Guaranteed-Return Crossover
Ordinary income tax: the tax a traditional 401(k) distribution owes, at your regular income tax rates, on the full amount withdrawn. — in Cashing Out a 401(k) When You Leave a Job — vs. Rolling It Over
Own-occupation / any-occupation: whether "disabled" means unable to do your job or unable to do any job; the single most valuable phrase in the policy's fine print. — in Disability Insurance: Insuring Your Paycheck, Not Just Your Stuff

P

Panic-selling: abandoning a long-term plan to sell during a decline, locking in the loss and usually missing the recovery. — in Behavioral Finance: Why We Sell at the Bottom
Pay yourself first: automate the savings slice off the top, before you can spend it. — in Budgeting & Cash Flow , Lifestyle Creep: Bank Your Raises or Spend Them?
Payday alternative loan (PAL): a small, regulator-capped short-term loan many credit unions offer as a deliberately cheaper substitute for a payday loan. — in Payday Loans: What a 'Small' Two-Week Fee Actually Costs
Payday loan: a small, short-term loan (commonly $100–$500, roughly two weeks) repaid in a lump sum on your next payday, priced as a flat fee rather than a stated interest rate. — in Payday Loans: What a 'Small' Two-Week Fee Actually Costs
Payment history: your record of paying on time; the largest single factor (35%). — in Credit Scores: What Actually Moves the Number
Payout rate: the annual income as a percentage of the premium; rises with the buyer's age. — in Annuities: Buying Yourself a Paycheck for Life
Per-purchase true cost: the same idea per item: one coffee's share of the nest egg the whole habit could have become. — in The Latte Factor: What a Small Daily Habit Really Costs
Phase-out (taper): withdrawing a benefit gradually as income rises instead of at a hard line. A gentle enough taper keeps the effective marginal rate under 100%, so a raise always helps. — in The Benefits Cliff: When a Raise Leaves You Worse Off
PITI: Principal, Interest, Taxes, and Insurance: the four parts of a housing payment that the 28% rule caps. (PMI and HOA dues, when they apply, count too.) — in How Much House Can You Actually Afford? The 28/36 Rule
PMI (private mortgage insurance): an extra monthly cost lenders usually require when you put down less than ~20%; it counts toward your ratios and shrinks affordability. — in How Much House Can You Actually Afford? The 28/36 Rule
Ponzi scheme: a fraud that pays existing investors with new investors' deposits rather than real profits, guaranteeing eventual collapse. — in Scams & Fraud: Spotting a Too-Good-to-Be-True Return
Positive / negative leverage: borrowing helps when the property out-earns the loan rate; it hurts when it doesn't. — in Real-Estate Investing: Cap Rate, Cash Flow, and the Magic (and Menace) of Leverage
PPO: higher premium, lower deductible, broader in-network flexibility than many HDHPs. — in HDHP + HSA vs PPO: Picking a Health Plan Without Guessing
Premium: what you pay (monthly or yearly) to keep a policy in force. — in Insurance: Buy Term and Invest the Difference , Options: Calls, Puts, and the Hockey-Stick Payoff , Annuities: Buying Yourself a Paycheck for Life
Premium / discount: a bond trading above par (because its coupon beats current rates) or below par (because its coupon trails them). — in Bonds: Why Their Prices Move Backwards
Present value (PV): what a future amount of money is worth today, after discounting for the return you could have earned in the meantime. The inverse of compounding. — in Present Value: Should You Take the Lump Sum or the Payments?
Price-to-rent ratio: the purchase price divided by a year's rent. High ratios favor renting; low ratios favor buying. — in Rent vs Buy: It's a Break-Even, Not a Battle
Principal: the money you start with or put in. — in Compound Interest & the Time Value of Money , Loans & Amortization
Principal paydown: the equity you build as the loan balance shrinks, paid for by your tenant's rent. — in Real-Estate Investing: Cap Rate, Cash Flow, and the Magic (and Menace) of Leverage
Promotional APR (intro APR): the temporary, often 0%, interest rate offered for a fixed window after the transfer. — in Balance Transfer: The 0%-APR Card That Becomes a Trap If You Miss the Deadline
PSLF (Public Service Loan Forgiveness): tax-free forgiveness after 10 years of qualifying payments while working for a government or nonprofit employer. — in Student Loans: Standard vs Income-Driven Repayment (and Forgiveness)
Purchasing power: how much real stuff a unit of money can buy. — in What Is Money & Inflation , Real Returns: What Your Money Is Actually Earning
Pyramid scheme: a Ponzi in which returns depend on recruiting new participants; each layer is funded by the one below it. — in Scams & Fraud: Spotting a Too-Good-to-Be-True Return

Q

Qualified medical expense: a cost the IRS lets you pay (or reimburse yourself for) from an HSA tax-free, from doctor visits and prescriptions to dental, vision, and Medicare premiums. — in The HSA: The Only Account With a Triple Tax Advantage
Quarterly estimated payments: the IRS payments (Form 1040-ES) a 1099 worker must send four times a year, since no employer withholds tax automatically. Underpaying risks a penalty even if the full balance is paid by the filing deadline. — in Gig Work & 1099s: The Self-Employment Tax Surprise

R

Rate caps (e.g. 2/2/5): limits on how much the rate can move: the first adjustment, each later adjustment, and the lifetime maximum above the starting rate. — in Adjustable-Rate Mortgages: The Teaser That Resets
Rate of return: the annual percentage your money grows. — in Compound Interest & the Time Value of Money
Re-amortize: recompute the payment by spreading the remaining balance over the remaining term at the new rate. Why a higher rate means a higher payment. — in Adjustable-Rate Mortgages: The Teaser That Resets
Real return: your return after inflation is taken out. Can be negative even when the nominal return is positive. — in What Is Money & Inflation , Real Returns: What Your Money Is Actually Earning , Savings Rate: The Shockingly Simple Math of Early Retirement
Real value: the inflation-adjusted value, in today's dollars. The one that matters. — in What Is Money & Inflation
Realized vs. unrealized: a paper (unrealized) loss does nothing for taxes until you sell and realize it. — in Tax-Loss Harvesting: Turning a Loser Into a Tax Break
Realized vs. unrealized gain: a gain is unrealized (and untaxed) while you hold; realized (and taxable) the moment you sell. — in Capital Gains: Why Holding On (and Trading Less) Beats the Tax
Rebalancing: periodically trimming what grew and topping up what lagged to restore your target mix, keeping your risk at the level you chose. — in Asset Allocation: How Much in Stocks vs Bonds?
Recency bias: the assumption that the recent trend will continue, which makes us greedy at tops and fearful at bottoms. — in Behavioral Finance: Why We Sell at the Bottom
Recovery asymmetry: the fact that recovering a loss of f requires a gain of f ⁄ (1 − f), always larger than the loss (down 50% needs +100%). — in Why a 50% Loss Needs a 100% Gain: Volatility Drag
Refinance: replacing an existing loan with a new one, usually at a different rate and term, paying off the old balance. You pay closing costs to do it. — in Refinancing a Loan: When Does It Actually Pay Off?
Refinancing: replacing your mortgage with a new one, usually to get a lower rate. Has its own closing costs, and so its own break-even. — in Mortgage Points: Buying Down Your Rate Is a Break-Even
Refund: money returned because you withheld more than you owed. Not a bonus — a refund of your own overpayment, lent to the government interest-free. — in Paycheck Withholding & the Tax-Refund Myth
Repayment period: the years after the draw ends, when the balance amortizes — principal and interest — over what's left. — in HELOC: Borrowing Against Your Home
Replacement rate: the fraction of gross pay the policy promises (commonly ~60%), before the cap and taxes have their say. — in Disability Insurance: Insuring Your Paycheck, Not Just Your Stuff
Reset / adjustment: the moment the ARM's rate changes after the intro period, on the schedule the second number names (yearly for a 5/1). — in Adjustable-Rate Mortgages: The Teaser That Resets
Residual value: what a car is still worth at the end of a lease or holding period. A lease's payment is set by the gap between the cap cost and this number. — in Buying a Car: New vs Used vs Lease
Revolving balance: debt with no fixed term that recalculates interest on whatever you currently owe, month after month. — in Credit Cards & the Minimum-Payment Trap
Risk premium: the extra expected return investors demand for holding a risky asset instead of a safe one. It's why the return exists at all: no risk, no premium. — in Risk & Return: Volatility Is the Price of Growth
Risk transfer: the core function of insurance: paying a small, certain cost to move a rare, ruinous loss onto the insurer. — in Insurance: Buy Term and Invest the Difference
Risk-adjusted return: an expected return discounted for its uncertainty. Because a guaranteed rate carries no risk, a risky investment should be expected to beat the debt rate by a margin before it's worth choosing over a sure payoff. — in Pay Down Debt or Invest? The Guaranteed-Return Crossover
Risk/return trade-off: the rule that higher expected returns come only with a wider range of possible outcomes. The width is the price; the return is what you're buying. — in Risk & Return: Volatility Is the Price of Growth
Rollover: redirecting a paid-off debt's minimum payment at the next target, so total outflow stays constant while per-debt firepower grows. — in Debt Payoff Strategies: Avalanche vs Snowball , Cashing Out a 401(k) When You Leave a Job — vs. Rolling It Over
Rollover (loan renewal): paying only the fee to extend a payday loan for another term, leaving the principal completely unpaid. — in Payday Loans: What a 'Small' Two-Week Fee Actually Costs
Roth (after-tax): contribute after tax (no deduction now), grow and withdraw completely tax-free. — in Retirement Accounts & the Employer Match: The Closest Thing to Free Money
Roth 401(k)/IRA: contributions are made with already-taxed money; qualified withdrawals in retirement are completely tax-free. — in Roth vs. Traditional: Pay the Tax Now, or Later?
Rule of 55: an exception that waives the 10% early-withdrawal penalty on a direct 401(k) cash-out (not an IRA) if you separate from that employer in or after the year you turn 55. — in Cashing Out a 401(k) When You Leave a Job — vs. Rolling It Over
Rule of 69 / 70: closer approximations for low or continuously-compounded rates, where the exact divisor is nearer 69.3. — in The Rule of 72: How Fast Does Money Double?
Rule of 72: the mental-math shortcut for doubling time. The divisor (72) is chosen to be easy to divide and most accurate around typical returns. — in The Rule of 72: How Fast Does Money Double?
Runway: savings ÷ monthly essentials: how many months you could cover with no income. — in The Emergency Fund

S

Savings rate: the share of your take-home pay you save rather than spend; the single biggest driver of how soon you reach financial independence. — in Savings Rate: The Shockingly Simple Math of Early Retirement , Lifestyle Creep: Bank Your Raises or Spend Them?
Self-employment tax: when you work for yourself, you pay both halves of FICA (~15.3%), which is why side-hustle income is taxed harder than wage income of the same size. — in Which Dollar Is Worth Most: A Raise, a Side Hustle, or Cutting Costs? , Gig Work & 1099s: The Self-Employment Tax Surprise
Self-insured: the point where your own savings are large enough to cover a loss yourself, so the insurance becomes unnecessary. — in Insurance: Buy Term and Invest the Difference
Selling costs: what it costs to sell, mostly the agent commission (~5–6%). It's why a quick resale almost always loses money. — in Rent vs Buy: It's a Break-Even, Not a Battle
Sequence-of-returns risk: the risk that the timing of returns, not just their average, changes your outcome. It only bites when money is flowing in or out; a buy-and-hold lump sum is immune. — in Sequence of Returns: Why a Crash Hurts More at the Finish Line
Short-term gain: a gain on an asset held one year or less, taxed at your ordinary income rate. — in Capital Gains: Why Holding On (and Trading Less) Beats the Tax
Shortfall: the expense's cost minus whatever's already saved toward it; the number the monthly set-aside actually has to close. — in Sinking Funds: Saving Monthly for the Bill You Know Is Coming , Paying for College: 529 Savings vs the Cost of Student Debt , Scams & Fraud: Spotting a Too-Good-to-Be-True Return
Single-premium immediate annuity (SPIA): the simplest kind: one lump-sum payment in, lifetime income starting right away. — in Annuities: Buying Yourself a Paycheck for Life
Sinking fund: money saved on a schedule for one specific, dated future expense, as opposed to an emergency fund (unpredictable shocks) or a budget (ongoing income allocation). — in Sinking Funds: Saving Monthly for the Bill You Know Is Coming
Snowball: paying minimums on everything, with every extra dollar to the smallest balance. Maximizes how soon the first debt disappears. — in Debt Payoff Strategies: Avalanche vs Snowball
Social Security wage cap: an income ceiling above which no more Social Security tax is owed; a raise above it stops paying the 6.2% SS portion. — in Which Dollar Is Worth Most: A Raise, a Side Hustle, or Cutting Costs? , Gig Work & 1099s: The Self-Employment Tax Surprise , Is a Second Income Worth It? The Childcare-and-Commute Math
Specific (idiosyncratic) risk: the risk unique to one asset or sector. Diversification's whole job is to cancel this out, because you aren't compensated for bearing it. — in Diversification: The Closest Thing to a Free Lunch
Spread: the gap between the buy and sell price on a trade or currency swap; a real, recurring cost even though it isn't labeled a "fee." — in Fees Everywhere: The Costs That Stack
Standard deduction: an amount subtracted from gross before income tax is figured, so the first chunk of income is untaxed. — in Income & Take-Home Pay
Standard plan: the default fixed payment that fully pays a federal loan off over 10 years: highest monthly bill, least total interest, debt-free fastest. — in Student Loans: Standard vs Income-Driven Repayment (and Forgiveness)
Stealth IRA: using the HSA as a long-term investment account by paying medical bills out of pocket, saving the receipts, and reimbursing yourself tax-free years later while the balance compounds. — in The HSA: The Only Account With a Triple Tax Advantage
Step-up in basis: at death, an heir's cost basis resets to the market value, often erasing the deferred gain entirely. — in Tax-Loss Harvesting: Turning a Loser Into a Tax Break
Sticker price: the published cost of attendance; what you actually pay can be lower after aid and scholarships, or higher after loan interest. — in Paying for College: 529 Savings vs the Cost of Student Debt
Stock / share: a unit of ownership in a company. As an owner you can be paid by the price rising and by dividends. — in Stocks: Price, Dividends & What 'Total Return' Really Means
Strike: the fixed price at which the option can be exercised. — in Options: Calls, Puts, and the Hockey-Stick Payoff
Student loan: money borrowed to pay for college, repaid with interest over a term (often 10 years); the same amortization math as any loan. — in Paying for College: 529 Savings vs the Cost of Student Debt

T

Take-home (net) pay: what actually lands in your account after withholding. — in Income & Take-Home Pay , Budgeting & Cash Flow
Take-home pay: what's left of your salary after federal income tax and FICA. See Income & Take-Home Pay. — in Two Job Offers: Compare Total Comp, Not Salary
Tax bracket: a band of income taxed at a given marginal rate. — in Income & Take-Home Pay
Tax deferral: legally delaying a tax you'll eventually owe, so the money keeps compounding for you in the meantime. — in Capital Gains: Why Holding On (and Trading Less) Beats the Tax
Tax drag: the wealth a taxable account quietly loses to taxes on its dividends and gains each year, which a tax-advantaged account avoids. — in Retirement Accounts & the Employer Match: The Closest Thing to Free Money
Tax-advantaged: describes an account whose growth the tax code shelters, so more of it compounds for you instead of going to taxes. — in Retirement Accounts & the Employer Match: The Closest Thing to Free Money
Tax-free growth: investment gains that are never taxed, so all of the compounding stays yours — the central advantage of a 529 over a plain taxable account. — in Paying for College: 529 Savings vs the Cost of Student Debt
Tax-timing bet: the entire Roth-vs-Traditional decision, reduced to one question: will your tax rate be higher or lower when you withdraw than it is when you contribute? — in Roth vs. Traditional: Pay the Tax Now, or Later?
Teaser rate: the low introductory rate an ARM is fixed at for its intro period, before the first reset. The rate on the billboard. — in Adjustable-Rate Mortgages: The Teaser That Resets
Term: how long the schedule runs; longer terms mean smaller payments but far more total interest. — in Loans & Amortization
Term life: pure, time-limited life insurance: cheap, covers a fixed window, builds no savings. — in Insurance: Buy Term and Invest the Difference
Term reset: restarting the payoff clock on a fresh, usually longer, schedule — which lowers the payment by spreading the balance over more months and can raise total interest even at a lower rate. — in Debt Consolidation: Does Trading Several Debts for One Actually Help? , Refinancing a Loan: When Does It Actually Pay Off?
The 4% rule / your number: a rule of thumb that a nest egg of ~25× your annual spending (one divided by a 4% safe withdrawal rate) can fund that spending more or less indefinitely. — in Savings Rate: The Shockingly Simple Math of Early Retirement
The employer match: the 7.65% share a W-2 employer pays on top of salary, invisible on a pay stub. A 1099 worker must fund this themselves out of the identical gross pay. — in Gig Work & 1099s: The Self-Employment Tax Surprise
The only free lunch: the nickname for diversification: a reduction in risk that costs nothing in expected return, available to anyone willing to not concentrate. — in Diversification: The Closest Thing to a Free Lunch
The premium-tax rule: employer-paid premiums make benefits taxable; premiums you paid with after-tax dollars make benefits tax-free. — in Disability Insurance: Insuring Your Paycheck, Not Just Your Stuff
Time diversification: the way a longer horizon lowers the chance of ending below where you started, by giving an asset's upward drift time to outweigh its year-to-year noise. — in Risk & Return: Volatility Is the Price of Growth
Time in the market: the idea that how long your money is invested matters more than catching the perfect entry point. The argument for lump sum, and against waiting. — in Dollar-Cost Averaging: Investing Through the Ups and Downs
Time in the market vs. timing the market: the principle that how long you stay invested matters far more than catching the perfect entry or exit. Behavioral finance is, mostly, a long argument for the former. — in Behavioral Finance: Why We Sell at the Bottom
Time value: the rest of the premium; the bet on further movement, which decays to zero by expiration. — in Options: Calls, Puts, and the Hockey-Stick Payoff
Time value of money: a dollar now is worth more than a dollar later, because it can start earning today. — in Compound Interest & the Time Value of Money
Too-good-to-be-true return: a steady, guaranteed, above-market yield; the single most reliable red flag of fraud, because real returns are neither steady nor guaranteed. — in Scams & Fraud: Spotting a Too-Good-to-Be-True Return
Total compensation: the full value of a job: salary plus the employer 401(k) match, benefits, bonuses, and equity, net of the costs you bear. Always bigger or smaller than the salary, never equal to it. — in Two Job Offers: Compare Total Comp, Not Salary
Total return: the complete measure of how a stock treated you: price change plus dividends. The only fair way to compare investments. — in Stocks: Price, Dividends & What 'Total Return' Really Means
Trade-off: the exchange itself: getting one thing by accepting less of another. — in Opportunity Cost & Trade-Offs
Tradeline: a single account entry on a credit report. A cosigned loan is one tradeline that appears, identically, on both the primary borrower's and the cosigner's report. — in Co-Signing a Loan: Vouching for Someone Else's Debt
Traditional (pre-tax): contribute before tax (a deduction now), grow tax-deferred, pay income tax on withdrawals in retirement. — in Retirement Accounts & the Employer Match: The Closest Thing to Free Money
Traditional 401(k)/IRA: contributions reduce taxable income now; withdrawals in retirement are taxed as ordinary income. — in Roth vs. Traditional: Pay the Tax Now, or Later?
Triple tax advantage: the HSA's defining feature: pre-tax in, tax-free growth, and tax-free out for medical. Every other account gives you at most two of the three. — in The HSA: The Only Account With a Triple Tax Advantage
True (annualized) APR: a fee stated as a share of a full year, computed the same way for any loan regardless of its actual term, which is what makes a two-week fee comparable to any other rate you'd see quoted. — in Payday Loans: What a 'Small' Two-Week Fee Actually Costs
True cost multiple: what each spent dollar would have become if invested; the receipt price times this multiple is the long-run price. — in Opportunity Cost & Trade-Offs , The Latte Factor: What a Small Daily Habit Really Costs
True cost of ownership: the all-in cost of owning a car over a period: cash paid in minus the resale value you keep, which equals depreciation plus financing interest. — in Buying a Car: New vs Used vs Lease
Turnover: the share of a portfolio bought and sold over a year; high turnover means frequent realized gains and more tax. — in Capital Gains: Why Holding On (and Trading Less) Beats the Tax

U

Underpayment penalty: interest the IRS charges when too little was withheld during the year, even if you pay the full balance by the deadline. — in Paycheck Withholding & the Tax-Refund Myth
Underwater / upside down: owing more on a loan than the asset is worth, so selling would require paying out of pocket. The hallmark of bad debt early in a loan's life. — in Good Debt vs Bad Debt: It's Not the Loan, It's What You Bought

V

Vested balance: the portion of your 401(k) that's fully yours, including any employer match that's cleared its vesting schedule; it's what plan-rule loan caps are based on. — in Borrowing From Your Own 401(k): The Loan That Sounds Free
Volatility: how much a price swings up and down over time. It's the raw material DCA turns into a discount — and, on the next lesson, the price you pay for higher returns. — in Dollar-Cost Averaging: Investing Through the Ups and Downs , Risk & Return: Volatility Is the Price of Growth
Volatility drag / variance drain: the gap between the arithmetic and geometric means; the compound growth lost purely to bumpiness, roughly σ²⁄2. — in Why a 50% Loss Needs a 100% Gain: Volatility Drag

W

W-4: the form that tells your employer how much to withhold. The dial you control; line 4(c) adds a flat extra amount per paycheck. — in Paycheck Withholding & the Tax-Refund Myth
Wash sale: buying the same or a substantially identical security within 30 days of the loss sale, which disallows the loss. — in Tax-Loss Harvesting: Turning a Loser Into a Tax Break
Whole life: "permanent" life insurance bundled with a slow-growing cash-value savings account; far more expensive for the same death benefit. — in Insurance: Buy Term and Invest the Difference
Windfall: a one-time, unbudgeted sum of money: a bonus, tax refund, inheritance, gift, or sale proceeds. — in You Just Got a Windfall: Where Should It Go?
Withholding: the income tax your employer removes from each paycheck and sends to the IRS as a prepayment toward your eventual bill. — in Paycheck Withholding & the Tax-Refund Myth
Writing (selling) an option: taking the seller's side: collect the premium, take on the obligation. — in Options: Calls, Puts, and the Hockey-Stick Payoff

Y

Yield: the return the market currently demands on a bond, which sets its price. When yields rise, prices fall, and vice versa. — in Bonds: Why Their Prices Move Backwards

Z

Zero-coupon bond: a bond that pays no coupons, just a single repayment at maturity, bought at a deep discount. It has the maximum duration for its maturity. — in Bonds: Why Their Prices Move Backwards

#

$3,000 ordinary-income offset: the most net capital loss you can deduct against ordinary income in one year; the rest carries forward. — in Tax-Loss Harvesting: Turning a Loser Into a Tax Break
401(k): a tax-advantaged retirement account offered through an employer, often with a match. — in Retirement Accounts & the Employer Match: The Closest Thing to Free Money
529 plan: a state-sponsored, tax-advantaged investment account for education: contributions grow tax-free and come out tax-free when spent on qualified college (and some K–12) costs. — in Paying for College: 529 Savings vs the Cost of Student Debt