Sports betting glossary
30 terms — every one written the way the NotaSportsGuru model uses it. One paragraph of context, the formula where there is one, and a worked example. Cross-linked so you can rabbit-hole the moment a definition raises another question.
Math & Probability
The difference between the line you bet and the closing line at the same book — the most predictive single metric of long-run edge.
The percentage-point gap between your win probability and the book's implied probability — your projected long-run advantage.
Expected value (EV) is the average profit or loss a bet pays per dollar staked if you repeated it under the same odds and probability forever.
The percentage of decided bets that won — excluding pushes.
The probability of a result that a sportsbook's odds are pricing in — calculated as one divided by the decimal odds.
The bet-sizing formula that maximises long-run bankroll growth, given an edge and a price.
The most common margins of victory in a sport — crossing them with a spread or hook adds disproportionate value.
Total profit divided by total stake, the cleanest single number for a sports bettor's performance.
The natural fluctuation of results around expected value — the reason a +EV strategy can still lose for weeks.
The sportsbook's built-in margin — the gap between the sum of implied probabilities across all outcomes and 100%.
Bet Types
A wager on a long-horizon outcome — championship winner, season MVP, regular-season win total — placed before or during the season.
Wagering on a game while it is in progress, with odds that update in real time based on the score, time remaining and momentum.
A straight bet on which team wins, with no point spread — priced via American odds where favorites are negative and underdogs are positive.
A single bet that combines two or more legs into one ticket — all legs must win for the parlay to pay.
A handicap a sportsbook adds to the underdog (or subtracts from the favorite) to make a moneyline mismatch into a roughly 50/50 market.
A bet on a specific event inside a game — most often a player stat over/under, but also team props or game props.
A bet that lands exactly on the line — neither winner nor loser. Stakes are refunded.
A bet that combines several legs into multiple smaller parlays — every possible 2-leg or 3-leg combination — instead of one big parlay.
A parlay-style bet where you adjust the spread or total in your favor on each leg in exchange for a worse price.
A bet on whether the combined score of both teams will go over or under a sportsbook-set number.
Strategy
Betting both sides of the same market at different sportsbooks where the prices guarantee a small profit regardless of outcome.
The dedicated pool of money a bettor uses to place wagers, kept separate from living expenses.
The favorite — the obvious pick, the side everyone is on, the team the line and the public agree about.
The team or side priced to lose — pays plus-money on the moneyline, gets points on the spread.
Placing a second bet on the opposite outcome of a live ticket to lock in profit or reduce risk.
Comparing prices at multiple sportsbooks to bet the best available number on every play.
A professional or professional-quality bettor — or the action that comes from one — typically defined by long-term profit and consistent closing line value.
The recreational or public bettor — or the action that comes from them — typically biased toward favorites, overs and household names.
A rapid, synchronized line move across multiple sportsbooks, usually triggered by sharp groups betting the same side simultaneously.
Betting only when your estimated win probability is higher than the bookmaker's implied probability.
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NotaSportsGuru publishes one curated +EV Parlay of the Day plus a full slate of player props and match lines, with every leg priced against the book and ranked by edge. Membership is by application.