Stock Market Glossary
Authoritative definitions of every term active equity traders and investors need — short squeeze mechanics, float, PDT rule, pre-market dynamics, VWAP, earnings reports, and more. Each entry includes examples and links to the free tools that apply the concept.
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Circuit Breakers & Trading Halts
Circuit breakers are automatic, exchange-mandated trading pauses triggered when market prices decline by predetermined thresholds, while trading halts are discretionary or regulatory pauses in individual securities due to pending news, volatility, or technical issues.
Float
Float is the number of shares of a company's stock that are available for public trading in the open market, calculated by subtracting insider holdings, restricted shares, and closely-held shares from total shares outstanding.
Level 2 Quotes
Level 2 quotes display the full depth of the order book for a stock — all outstanding bid and ask orders beyond the best inside bid and ask, showing the price and size of orders at multiple price levels across all market makers and electronic venues.
Pattern Day Trader Rule
The Pattern Day Trader (PDT) rule is a FINRA regulation requiring any U.S. trader who executes four or more day trades within five business days in a margin account — when those trades represent more than 6% of total trading activity — to maintain a minimum account equity of $25,000.
Pre-Market & After-Hours Trading
Pre-market trading occurs before the official NYSE/NASDAQ open (9:30 AM ET) from 4:00-9:30 AM ET, and after-hours trading occurs from 4:00-8:00 PM ET after the close, both featuring lower liquidity, wider spreads, and price discovery driven primarily by earnings announcements and breaking news.
Short Interest
Short interest is the total number of shares of a stock that have been sold short and not yet covered or closed out, expressed as an absolute share count and as a percentage of float, serving as a measure of bearish market sentiment toward a security.
Short Squeeze
A short squeeze is a rapid, self-reinforcing price surge driven by short sellers being forced to buy shares to cover losing positions, amplifying upward price momentum far beyond what fundamental catalysts alone would produce.
Fundamental Analysis
Dividend Yield
Dividend yield is the annual dividend paid by a company expressed as a percentage of the current share price, representing the cash return an investor receives from dividends alone, independent of any price appreciation or depreciation.
Earnings Per Share (EPS)
Earnings Per Share (EPS) is the portion of a company's net profit allocated to each outstanding share of common stock, calculated by dividing net income by the weighted average number of diluted shares outstanding, serving as the primary measure of corporate profitability on a per-share basis.
IPO — Initial Public Offering
An Initial Public Offering (IPO) is the process by which a private company first offers shares to the general public on a regulated stock exchange, raising capital and enabling founders, employees, and early investors to achieve liquidity for their ownership stakes.
Market Capitalisation
Market capitalisation is the total market value of a company's outstanding shares, calculated by multiplying the current share price by the total number of shares outstanding, used to classify companies as large-cap, mid-cap, or small-cap and to weight stocks in indices.
P/E Ratio
The Price-to-Earnings (P/E) ratio is the most widely used equity valuation metric, calculated by dividing a stock's current market price by its earnings per share (EPS), indicating how much investors are willing to pay for each dollar of current earnings.
Technical Analysis
52-Week High & Low
The 52-week high and low are the highest and lowest prices at which a stock has traded during the preceding 52 calendar weeks, serving as widely referenced technical reference points for momentum assessment, breakout identification, and mean-reversion analysis.
VWAP (Stocks)
VWAP (Volume-Weighted Average Price) is the average price of a stock weighted by trading volume over a specified period, typically the current trading day, used by institutional traders as a benchmark for execution quality and by technical traders as a dynamic support and resistance level.
Why Every Crypto Trader Needs a Strong Vocabulary
Crypto trading has its own language. Exchanges, analysts, and educators throw around terms like leverage, liquidation, margin, perpetual futures, and dollar-cost averaging as if everyone already knows what they mean. Many traders — including experienced ones — misunderstand key concepts, and those misunderstandings cost real money.
This glossary covers the concepts that matter most to active traders: the mechanics of leveraged positions, how liquidation works, why position sizing is the single most important risk control, and how tools like stop-losses and take-profit orders protect your capital. Every definition includes a practical example and links to free calculators so you can immediately apply what you learn.
Whether you're just starting out in crypto trading or you've been at it for years, building a precise understanding of these terms will sharpen your decisions and protect your capital. Use the DennTech blog alongside this glossary for deeper dives into trading strategy, and use the free tools to put every concept to work immediately.