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Invest Glossary

Plain-English definitions of investing and stock-market terms — read one, and you will understand it for good. Built by an independent investor for anyone who wants the honest, jargon-free answer, whether you are buying your first fund or managing a portfolio for years.

InvestGlossary is an independent, ad-supported reference built for one reader: the person who hears a financial term and wants a clear, honest answer in plain English. Every entry opens with a one-sentence definition, then walks through the formula, a worked example with real numbers, the common misunderstandings, and how investors actually use the idea in practice. No jargon for its own sake, no sales pitch — just definitions written by an independent investor and reviewed before publication. The site is organised into five topic areas — valuation, funds, bonds, trading, and risk — so related ideas sit next to each other and build on what you already know, and the A–Z index lets you jump straight to any term by its first letter. New terms are added over time, and each addition follows the same structure: a definition you can act on, numbers you can check, and the mistakes people make. If a concept is missing, send us a note and we will add it.

120Terms defined
5Topic categories
480Answered questions
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Valuation multiples, profitability, and financial ratios

Stock Value

28 terms

P/E Ratio (Price-to-Earnings)

The P/E ratio tells you how much investors pay for each dollar a company earns. A higher P/E means the market expects…

EPS (Earnings Per Share)

EPS shows how much profit a company made for each share you own. It is net income divided by the number of shares out…

PEG Ratio

PEG adjusts the P/E ratio for expected earnings growth, so a stock’s price looks fairer once growth is considered.

Market Capitalization

Market cap is the total value of a company’s shares: its share price multiplied by the number of shares outstanding.

P/B Ratio (Price-to-Book)

P/B compares a stock’s price with the accounting value of its net assets per share.

ROE (Return on Equity)

ROE measures profit generated for each dollar of shareholders’ equity.

Show all 28 terms

Index funds, ETFs, sectors, and portfolio structure

Funds & ETFs

17 terms

ETF (Exchange-Traded Fund)

An ETF is a basket of securities that trades on an exchange like a single stock, giving instant diversification.

Mutual Fund

A mutual fund pools investor money to buy a managed basket of securities, priced once daily after the market closes.

Index Fund

An index fund aims to match a market index’s return rather than beat it, by holding the same stocks in the same weights.

Expense Ratio

The expense ratio is the annual fee a fund charges, taken from your returns as a percentage.

S&P 500

The S&P 500 is a cap-weighted index of 500 large U.S. companies, the default gauge of the American market.

Diversification

Diversification is spreading money across assets so one bad bet cannot sink the whole portfolio.

Show all 17 terms

Fixed income, yield curve, central-bank policy, and inflation

Bonds & Rates

16 terms

Bond Yield

Bond yield is the return an investor gets from a bond, usually as a percentage of its price.

Yield Curve

The yield curve plots bond yields across maturities; its slope signals growth and rate expectations.

Bond Duration

Duration estimates how much a bond’s price moves for a 1% change in interest rates.

Interest Rate

An interest rate is the cost of borrowing or the reward for lending, set by markets and central banks.

Inflation

Inflation is the rise in prices over time, quietly shrinking the buying power of cash.

Credit Rating

A credit rating is an agency’s grade of a borrower’s ability to repay debt, from rock-solid to distressed.

Show all 16 terms

Order types, derivatives, technicals, and IPOs

Trading & Markets

23 terms

Market Order

A market order buys or sells immediately at the best available price, with no price limit.

Limit Order

A limit order only executes at your specified price or better, protecting you from bad fills.

Options

Options are contracts giving the right, not the obligation, to buy or sell a stock at a set price before a date.

IPO (Initial Public Offering)

An IPO is a private company’s first sale of shares to the public, listing it on an exchange.

Stock (Share)

A stock is a slice of ownership in a company; holders share in its profits and losses.

Volatility

Volatility is how much a price swings up and down over time, usually measured by standard deviation.

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Volatility, drawdowns, rebalancing, and macro cycles

Portfolio & Risk

25 terms

Volatility

Volatility is how much a price swings up and down over time, usually measured by standard deviation.

Beta (Stock Volatility vs Market)

Beta measures how much a stock tends to move compared with the overall market. 1.0 moves with the market; above 1 swi…

Sharpe Ratio

The Sharpe ratio measures excess return per unit of total risk, so you can compare funds on equal risk footing.

Drawdown

Drawdown is the peak-to-trough loss from a high point to the next low, a blunt measure of pain.

Diversification

Diversification is spreading money across assets so one bad bet cannot sink the whole portfolio.

Asset Allocation

Asset allocation is how you split money across stocks, bonds, cash, and alternatives.

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