60+ terms covering betting math (no-vig, devig, CLV, overround), market structure (sharp vs square, arbitrage, middling, alt-lines), and API integration (rate limits, idempotency keys, WebSocket, SSE). Includes schema.org DefinedTerm markup so AI search and Google rich snippets can quote individual definitions.
A sportsbook price with the bookmaker's overround (vig) mathematically stripped out, leaving the implied fair probability before commission. Used as the fair-value reference in +EV scanning. See no-vig CLV explained.
The process of normalizing the two sides of a two-way market so their implied probabilities sum to 1.0, removing the bookmaker's hold. Mathematically: p_no_vig = p_implied / (p_home_implied + p_away_implied).
The bookmaker's commission embedded in the prices. The amount by which the sum of implied probabilities exceeds 1.0. Standard US sportsbook vig on a moneyline is ~4.76% (the gap from -110/-110 to 50/50).
The bookmaker's expected profit margin, computed as overround divided by the sum of all implied probabilities. Distinct from vig only on multi-way markets where the math differs.
The difference between the price you took on a bet and the closing price of the same market. Positive CLV is the strongest single correlate of long-run betting profitability. See closing-line snapshot conventions.
Closing-line value computed against the sharp book's devigged closing probability rather than the vigged closing price. The professional grading convention. Avoids double-counting the vig.
The probability of an outcome that's implied by the offered odds. For American odds: positive prices use 100/(price+100); negative prices use |price|/(|price|+100).
A bet-sizing formula that scales stake to the bettor's perceived edge and bankroll, theoretically maximizing long-run logarithmic growth. fraction = (bp - q) / b where p is win prob, q is lose prob, b is decimal odds minus 1.
The price posted by the sharp book in the final seconds before the market is removed (typically at event commence_time). The reference for CLV grading.
A bet where your estimated win probability exceeds the implied probability of the price taken. Long-run profitable; not necessarily on the individual bet. See /ev and reading +EV outputs honestly.
A sportsbook (Pinnacle, Circa, Bookmaker.eu, BetCRIS) that takes high-limit action from informed bettors and continuously reshapes lines in response. Sharp prices are the public proxy for fair value.
A retail-focused sportsbook (DraftKings, FanDuel, BetMGM) that takes most action from recreational bettors and models prices to balance entertainment and profit.
A peer-to-peer betting marketplace where users back and lay outcomes against each other rather than betting against the house. Examples: Smarkets, Matchbook, Betfair.
The maximum stake a sportsbook will accept on a given market from a given account. Sharp accounts get higher limits; flagged-for-value accounts get reduced limits.
A temporary state where a live market is offline because the book's risk engine cannot price it (during plays, injuries, reviews). Prices return when the book resumes.
A bidirectional connection protocol that allows the server to push updates without polling. Used for sub-second odds streaming. See /docs/websocket and the live demo at /ws-demo.
A unique per-request identifier sent in the Idempotency-Key header. The server returns the same response for any retry with the same key, making writes safe to retry.