Sports betting glossary: every term explained, a to z

A complete reference for betting terminology - with links to the full, in-depth guide wherever this site has already covered a concept in detail

This glossary is built to be genuinely fast to use: a clear, one-to-two sentence definition for every term, with a link through to a complete dedicated guide anywhere this site has already covered the concept in real depth. If you just need to know what a word means, it's here. If you want the full mechanics, worked examples, and strategic context, follow the link.

A

Action - Having an active wager placed on an event.

Against the Spread (ATS) - A team's win/loss record measured against the point spread rather than the final outcome. A team that's 8-4 ATS has covered the spread 8 times in 12 games, regardless of their actual win/loss record.

Alternate Line - A spread, total, or other market offered at a different number than the standard line, priced accordingly - a shorter spread costs worse odds, a longer one pays better.

Arbitrage - Betting every outcome of an event across different bookmakers to lock in a guaranteed profit, exploiting a gap between two operators' independently-set prices. → Full explanation in our guide to reading betting odds.

Ante-Post - A UK term for a bet placed well in advance of an event, most commonly horse racing. → Covered in our each-way betting guide.

Asian Handicap - A football (soccer) betting format that removes the draw as a possible outcome entirely, using quarter-, half-, or whole-goal handicaps (e.g. -0.25, -0.5, -0.75) to level a matchup between two sides. Unlike a standard point spread, a quarter-goal handicap (e.g. -0.25) effectively splits your stake across two adjacent lines, meaning part of your bet can win, lose, or push independently of the rest - a distinctly different settlement mechanic from any other handicap format covered in this glossary. Compare with European Handicap, below.

B

Backdoor Cover - A team that wasn't covering the spread scores unexpectedly late - often in garbage time - to cover it after all.

Bad Beat - Losing a bet that looked certain to win until a very late, often unlikely, turn of events.

Banker - In a system bet, a selection you're highly confident in, included in every combination within the system. → Covered in our accumulator betting guide.

Bankroll - The total amount of money set aside specifically for gambling, kept separate from other funds. → Full guide: bankroll management.

Big/Small - An even-money bet in Sic Bo (and, with different number ranges, Fan Tan) on whether a result falls in the lower or upper half of the possible range. → Covered in our Sic Bo and Fan Tan guide.

Book / Sportsbook - Short for bookmaker or the wagering platform itself.

Buy Points - Paying extra vig to move a spread or total to a more favourable number.

C

Cash Out - Settling a bet before the event concludes, for an amount the bookmaker calculates based on the bet's current live probability. → Full guide: Cash Out explained.

Chalk - The favourite. A "chalky" slate is one where favourites are heavily backed across the board.

Chalk Eater - A bettor who consistently backs favourites.

Circled Game - An event where a sportsbook has reduced its betting limits, typically due to uncertainty around injuries, weather, or other factors affecting the line's reliability.

Closing Line - The final odds available on a market immediately before an event begins, widely regarded as the most efficiently priced number available since it reflects all information and action absorbed up to that point. → Full explanation in our guide to reading betting odds.

Closing Line Value (CLV) - The difference between the price you took and the closing price on that same market; consistently capturing positive CLV is considered the professional standard for measuring genuine betting skill. → Full explanation in our guide to reading betting odds.

Correlated Parlay / Correlated Legs - Parlay legs whose outcomes influence one another, requiring specialised pricing rather than simple independent-odds multiplication. → Full guide: Same Game Parlay explained.

Cover - When a spread bet wins: the favourite winning by more than the spread, or the underdog losing by less than the spread (or winning outright).

D

Dead Heat - A tie between multiple competitors in an individual sport, such as golf, requiring a specific settlement rule for place-based bets.

Decimal Odds - An odds format showing total return (stake included) per unit staked, standard across Europe and widely offered by UK operators. → Full explanation in our guide to reading betting odds.

Dog (Underdog) - The side expected to lose, shown with a "+" sign on the moneyline and spread.

Drift - When a betting line moves against the price you took, meaning the market ultimately valued your position as worse than what you accepted. → Full explanation in our guide to reading betting odds.

E

Each-Way - A bet split into two parts: half on a selection to win outright, half on it to place. → Full guide: each-way betting explained.

Even Money - A bet with no juice built in either direction, paying exactly what you staked in profit - +100 in American odds, 2.00 in decimal, evens (1/1) in fractional.

Exposure - The total amount a sportsbook stands to lose on a specific outcome.

F

Fade - Betting against the popular or public side of a market.

Favourite - The side expected to win, per the oddsmakers' assessment.

Fixed-Limit - A poker betting structure where bet sizes are predetermined for each round. → Full guide: poker hand rankings and Texas Hold'em rules.

Fractional Odds - The traditional UK odds format, showing profit relative to stake as a fraction (e.g. 5/1). → Full explanation in our guide to reading betting odds.

European Handicap - A whole-number handicap format that, unlike Asian Handicap, still allows for a draw outcome - the more traditional three-way (win/draw/win) handicap structure.

Futures - A bet on a long-term outcome decided well in advance, such as a season-ending championship winner - carries more risk than a standard bet given the extended time before settlement.

Getting Down - Successfully placing a bet, particularly a large one, before a sportsbook adjusts its limits or the line moves.

Grand Salami - A bet on the combined total score across every game in a specific sport on a given day, rather than a single event.

Gubbing (Getting Gubbed) - A UK term for having your account restricted or limited by a bookmaker, typically applied to bettors an operator identifies as consistently winning.

H

Handicap - A points advantage or disadvantage applied to one side of a matchup to level the betting proposition. See also Asian Handicap and European Handicap, above.

Handle - The total amount of money wagered at a sportsbook or on a specific market.

Hedging - Placing an additional bet on the opposite outcome of an existing wager, typically after favourable movement, to guarantee a profit or reduce a loss. → Full explanation in our guide to reading betting odds.

Hold - The percentage of total handle a sportsbook retains as profit after all bets are settled - the sports-betting-operations equivalent of house edge.

Hook - The extra half-point added to a spread or total specifically to prevent a push - the difference between a line of -7 and -7.5.

House Edge - The percentage of all wagered money a casino game or bet structurally retains over the long run; the inverse of RTP. → Full guide: RTP and house edge explained.

I

Implied Probability - The likelihood of an outcome as suggested by its odds, calculated directly from the price. → Full explanation in our guide to reading betting odds.

In-Play / Live Betting - Wagering on a market after an event has already begun, with odds updating continuously as the event unfolds.

J

Juice / Vig / Vigorish - The bookmaker's built-in commission on a bet, the mechanism by which a sportsbook guarantees itself a structural edge. Also called the overround. → Full explanation in our guide to reading betting odds.

K

Key Numbers - Specific point-spread values (3 and 7 in NFL football, in particular) that a line crosses more consequentially than other numbers, because they correspond to unusually common margins of victory. → Full explanation in our guide to reading betting odds.

Kelly Criterion - A formula calculating the mathematically optimal bankroll fraction to stake on a bet with a genuine, quantifiable edge. → Full guide: bankroll management.

L

Lay Odds - In craps, an additional bet behind a Don't Pass or Don't Come wager, paying less than even money to reflect the improved probability of that side. → Full guide: craps rules and strategy.

Line Shopping - Checking a bet's price across multiple bookmakers before placing it, to secure the best available number. → Full explanation in our guide to reading betting odds.

M

Middling - Betting both sides of a line at two different numbers, structured so a specific narrow range of outcomes wins both bets simultaneously.

Moneyline - A bet on which side wins outright, with no spread involved; the standard American odds format. → Full explanation in our guide to reading betting odds.

N

Nap - A tipster's or handicapper's specifically suggested best bet of the day.

No Purchase Necessary - The legal structure underpinning US sweepstakes casinos, where a free entry method must exist alongside any paid option.

O

Odds - The price attached to a bet, reflecting both potential payout and implied probability. → Full guide: how to read betting odds.

Odds Bet (Free Odds) - In craps, an additional wager behind a Pass Line or Come bet that pays true mathematical odds with zero house edge - the only such bet in any casino. → Full guide: craps rules and strategy.

Overround - The amount by which a market's combined implied probabilities exceed 100%, representing the bookmaker's structural margin. → Full explanation in our guide to reading betting odds.

Over/Under (Total) - A bet on whether the combined score of both teams/competitors will exceed or fall short of a number set by the sportsbook.

P

Parlay - The American term for an accumulator - multiple selections combined into one wager, requiring every leg to win. → Full guide: accumulator betting explained.

Pick'em - A matchup with no clear favourite, priced close to even on both sides.

Point Spread - A handicap applied to the favourite to level a matchup for betting purposes. → Full explanation in our guide to reading betting odds.

Prop Bet (Proposition Bet) - A wager on a specific occurrence within an event, not tied to the final outcome - a player's statistical total, for example.

Provably Fair - A cryptographic system letting a player independently verify a specific bet's fairness themselves, common at crypto casinos. → Full guide: how random number generators work.

Push - A tie against a spread or total, resulting in stakes being returned rather than a win or loss.

R

RTP (Return to Player) - The percentage of all wagered money a casino game returns to players over its full theoretical lifetime. → Full guide: RTP and house edge explained.

Rule 4 - A UK horse racing deduction applied to winnings when a horse is withdrawn from a race after you've placed a bet. → Full guide: each-way betting explained.

S

Same Game Parlay (SGP) - A parlay built entirely from multiple markets within a single game, priced with correlation-aware algorithms rather than simple independent-odds multiplication. → Full guide: Same Game Parlay explained.

Sharp / Wiseguy - A professional or highly skilled bettor, often used as a reference point for where the smart money is moving.

Square - A casual or recreational bettor, generally understood as the opposite of a sharp.

Straight Bet - A single wager on one outcome, with no other legs or conditions attached.

Steam - A sudden, significant line movement, typically caused by a wave of money - often perceived as sharp - hitting one side of a market. → Full explanation in our guide to reading betting odds.

Sticky Bonus - A casino bonus that can be used to play and win with, but whose principal amount can never itself be withdrawn. → Full guide: wagering requirements explained.

System Bet - A cover-bet structure (Trixie, Yankee, Patent, Canadian, Heinz, Goliath) combining multiple smaller bets from a set of selections, providing partial returns even if not every selection wins. → Full guide: accumulator betting explained.

T

Taking Points - Betting on the underdog side of a spread.

Laying Points - Betting on the favourite to cover the spread (the opposite of Taking Points, included here for direct contrast despite alphabetical placement).

Team Total - A bet on a single team's individual score, rather than the combined total of both sides.

Teaser - A multi-leg bet where you adjust the spread or total in your favour on every leg - moving a -7.5 spread to -1.5, for example - in exchange for meaningfully shorter combined odds than a standard parlay would offer for the same legs at their original numbers. Every leg must still win. Teasers feel safer than parlays because each individual leg is easier to hit, but the shortened payout reflects that increased safety - the underlying house edge doesn't disappear, it's simply repriced into the reduced odds.

Ticket % - The share of total bets (by count, not necessarily by dollar amount) placed on a specific side of a market - a measure of public sentiment distinct from handle.

Total - See Over/Under.

U

Under - A bet that the combined score will fall short of the posted total.

Underdog - See Dog.

Unit - A standardised bet size, typically 1–5% of total bankroll, used to keep risk consistent as a bankroll grows or shrinks. → Full guide: bankroll management.

V

Vig / Vigorish - See Juice.

Void - A bet cancelled and refunded due to specific circumstances - a postponed match, a non-runner, or another rule-defined disruption.

Volatility - How widely a casino game's individual outcomes vary around its long-run average return; distinct from RTP itself. → Full guide: RTP and house edge explained.

W

Walkover - A win awarded automatically due to an opponent's withdrawal, rather than through actual competition.

Wagering Requirement - The total amount you must bet before a casino bonus, or winnings generated from it, become withdrawable. → Full guide: wagering requirements explained.

Win Percentage (Break-Even Percentage) - The win rate required at a given price just to break even - 52.38% at standard -110 odds, for example. → Full explanation in our guide to reading betting odds.

Z

Zip Price - Informal term for +100 (even money) in American odds.

Frequently asked questions

What does "chalk" mean in sports betting?

The favourite. A "chalky" slate describes a set of games where favourites are heavily backed across the board - the term originates from the historical practice of chalking odds onto a board.

What's the difference between a parlay and a teaser?

A parlay (called an accumulator in the UK) combines selections at their original odds, multiplied together, with every leg required to win. A teaser lets you shift the spread or total in your favour on every leg - making each individual leg easier to win - in exchange for meaningfully shorter combined odds than a standard parlay would pay for the same legs.

What does it mean when a game is "circled"?

A sportsbook has reduced its betting limits on that specific event, typically due to uncertainty - often injury news, weather conditions, or other factors that make the sportsbook less confident in its own posted line.

What is "juice" or "vig" in betting?

The bookmaker's built-in commission, embedded directly into the odds rather than charged as a separate fee - the mechanism that gives a sportsbook a structural mathematical edge on every market regardless of the outcome.

What does it mean to "cover the spread"?

For a favourite, winning by more points than the spread. For an underdog, either losing by fewer points than the spread or winning outright. A bet on a team that "covers" wins the spread bet regardless of whether that team actually won the game.

This glossary is for educational purposes. Gambling problem? In the UK: BeGambleAware.org | 0808 8020 133. In the US: 1-800-GAMBLER. Information correct as of September 2026.