Sports Betting Glossary — A to Z of Terms

A

Accumulator: British term for a parlay — a single bet combining multiple selections, all of which must win for the bet to pay out. Each leg's odds multiply together. See the Parlay Calculator.
Action: Any wager you have on a game. "I have action on the Lakers" means you have a bet on the Lakers. Sportsbooks also call total betting volume on a market "action."
American Odds: The U.S. moneyline format. Positive numbers (e.g. +150) show how much a $100 bet wins. Negative numbers (e.g. −200) show how much you risk to win $100. Convert to other formats with the Odds Converter.
Arbitrage (Arb / Sure Bet): Betting on every possible outcome of an event across different sportsbooks at prices that guarantee profit. Edges are typically 0.5–3% and short-lived. See the Arbitrage Calculator.
Asian Handicap (AH): A football (soccer) handicap market that removes the draw by giving one side a virtual goal start. Lines come in whole, half, and quarter increments. The Asian Handicap Calculator covers all three.
ATS (Against The Spread): A team's record relative to the point spread, not just outright wins/losses. A team that's 7-3 ATS has covered the spread in 7 of 10 games.

B

Back: A traditional bet that an outcome WILL happen, placed at a sportsbook. The opposite of a Lay. Used in Matched Betting and exchange terminology.
Backdoor Cover: When a team scores a meaningless late-game point or touchdown that pushes them across the spread without affecting the win/loss outcome. Heaven for spread bettors, hell for the other side.
Bankroll: The total money you've set aside for betting, separate from living expenses. Disciplined bettors size individual bets as a percentage of bankroll (typically 1–5%) to manage variance.
Bet Slip: The on-screen panel where you confirm and place your bet. Most sportsbooks let you save selections to the slip without committing.
Bookmaker (Bookie): A licensed business that sets odds and accepts wagers. In the U.S. they're called sportsbooks; in the U.K. and Ireland, bookmakers or "bookies."
Buy Points: Adjusting a point spread or total in your favor by paying a worse price. Buying half a point on −3 to −2.5 typically costs an extra 10 cents of juice.

C

Cash Out: Settling a live bet before the event finishes, for an amount the sportsbook calculates based on current market prices. Almost always at a worse price than fair value.
Chalk: The favorite. "Chalk eaters" are bettors who consistently bet favorites without regard to value.
Closing Line: The final odds before a market locks. Used as a benchmark — sharp bettors aim to consistently beat the closing line, which correlates with long-term profitability.
Closing Line Value (CLV): The difference between the price you got and the closing line. Positive CLV is a sign of a winning long-term approach.
Commission: The fee a betting exchange charges on net winnings. Typical 2–5% on the major exchanges. Critical to factor into matched betting calculations.
Cover: To win a point-spread bet by the required margin. "The Patriots covered" means they beat the spread, not just won the game.

D

Dead Heat: When two or more selections finish tied. Dead-heat rules typically pay out at full odds on a reduced stake (stake ÷ number of tied selections).
Decimal Odds: European/global format showing total return per unit including stake (e.g. 2.50 means $2.50 back per $1 staked, or $1.50 profit). The easiest format for arithmetic. Convert to American.
Dime Line: A market with 10 cents of juice between the favorite and underdog (e.g. −105/+95). Tighter than the standard 20-cent line (−110/−110 or −115/−105).
Dog: Short for underdog. The team or player priced at plus-money in American odds, or above 2.00 in decimal.
Double Chance: A football (soccer) market that bundles two of three 1X2 outcomes — Home or Draw, Home or Away, or Draw or Away — at lower odds.
Draw No Bet (DNB): A football market that returns your stake if the match ends in a draw. Mathematically equivalent to Asian Handicap 0.

E

Each-Way: A horse-racing bet split into two halves: a Win bet and a Place bet. If the horse wins, both halves pay; if it places, only the Place half pays at reduced fractional terms (e.g. 1/4 odds on top 4). See the Each-Way Calculator.
Edge: The percentage advantage a bettor (or the house) has over fair odds. Sharp bettors look for edges of 2–5%; books typically build in 4–8% edge via vig.
EV (Expected Value): The long-run average outcome of a bet. Positive EV (+EV) means the bet wins money on average; negative EV (−EV) means it loses. Calculated as (probability × payout) − (1 − probability) × stake.
Even Money (Evens): Odds of 1/1, +100 American, or 2.00 decimal. A $1 stake returns $2 total ($1 profit). Implied probability 50%.
Exchange (Betting Exchange): A peer-to-peer platform where users back AND lay against each other rather than against the house. Required for matched betting Lay positions.
Exotic Bet: Any bet beyond a straight win/loss — parlays, teasers, props, futures, and most racing combos like trifectas and exactas.

F

Fade: To bet against a particular team, player, or tipster. "Fade the public" is a strategy of betting opposite to popular money.
Favorite: The team or player the sportsbook expects to win. Priced at minus-money in American odds, below 2.00 in decimal.
First Half (1H): A bet that settles based only on the first half of a game, ignoring the second half and overtime.
Fold: British term for the number of legs in a parlay or system bet — "five-fold accumulator" means a 5-leg parlay.
Fractional Odds: The traditional UK and Irish format expressing profit-per-stake (e.g. 3/2 means $3 profit per $2 staked). Common in horse racing. Convert to decimal.
Free Bet: A promotional credit that pays only the winnings (Stake Not Returned), or rarely the winnings plus stake (Stake Returned). The cornerstone of matched betting.
Futures: Long-term bets on outcomes that resolve weeks or months later — Super Bowl champion, Premier League winner, MVP awards. Tied-up bankroll and high vig.

G

Goliath: A system bet of 247 wagers across 8 selections — every double, treble, four-fold, five-fold, six-fold, seven-fold, and eight-fold combination. Available in the System Bets section.
Graded Bet: A bet that has been settled (won, lost, pushed, or voided) by the sportsbook.
Grand Salami: A single bet on the over/under of total goals or runs across all games on a given day, common in NHL and MLB.
Gubbed: Slang for being restricted by a sportsbook — typically banned from bonuses and limited to small stakes — due to suspected promo abuse or being identified as a sharp/arbitrage bettor.

H

Half-Time/Full-Time (HT/FT): A combined bet on the result at half time and at full time (e.g. Home/Home, Draw/Away). Typically priced at long odds.
Handicap: A virtual goal/point start given to one side to even out the market. See Asian Handicap Calculator and Spread/Point Spread.
Handle: The total amount of money a sportsbook accepts on a market, an event, or in a given period.
Heinz: A system bet of 57 wagers across 6 selections — every double, treble, four-fold, five-fold, and six-fold. Named after the "57 varieties" Heinz slogan.
Hedge: Placing a second bet to reduce risk on an existing position — typically near event end to lock in some profit or limit losses.
Hook: The half-point on a spread or total, e.g. −7.5. Crucial in NFL where many games land exactly on 3 or 7 (key numbers).

I

If Bet: A two- or multi-bet structure where the second bet only places if the first wins. Reduces exposure on parlays at the cost of upside.
Implied Probability: The probability a price implies. Calculated as 1 ÷ decimal odds (or 100 ÷ (odds + 100) for + American). Built into the Odds Converter.
In-Play (Live Betting): Bets placed after an event has started. Lines move every second based on the action; latency and limits are tighter than pre-match.

J

Juice (Vig / Vigorish): The sportsbook's built-in margin. On a market where both sides should be even money, the book offers −110/−110 instead of +100/+100 — the 10 cents difference is the juice.
Jolly: British slang for the favorite, especially in horse racing.

K

Kelly Criterion: A formula for optimal bet sizing given an edge: (edge ÷ odds). Maximizes long-term geometric growth of bankroll. Most professionals use Half-Kelly to dampen variance.
Key Number: The most common margin of victory in a given sport. NFL key numbers: 3 and 7. NBA: 4 and 7. Crucial for spread strategy and the Teaser Calculator.

L

Lay: A bet that an outcome will NOT happen, placed on a betting exchange. The opposite of a Back. Lay liability = lay stake × (lay odds − 1).
Limit: The maximum a sportsbook will accept on a single bet or market. Limits reflect the book's confidence in the line — higher limits = sharper line.
Line: The published price/spread/total on a market. "The line moved from −7 to −7.5" means the spread tightened.
Lock: Slang for a bet with a perceived high probability of winning. There are no real locks in sports betting — but the term gets thrown around.
Lucky 15 / 31 / 63: System bets covering 4, 5, and 6 selections respectively, including all multiples plus singles. Many UK books offer bonuses for hitting all selections. See the Parlay/System Bets section.

M

Margin: 1) The percentage built-in profit of a sportsbook (~5% typical), calculated as the sum of inverse decimal odds minus 1. 2) The score difference in a game.
Matched Betting: A technique that uses Back/Lay pairs to convert sportsbook free-bet promotions into near-guaranteed profit. See the Matched Betting Calculator.
Middle: A two-bet structure where both bets can win — e.g. betting Over 47 and Under 50 on the same game. If the total lands on 48 or 49, both win (a "middle"). Otherwise one wins and one loses, costing only the vig.
Money Line: A bet on an outright winner with no spread or handicap. Priced in American odds. The simplest sportsbook bet.
Multiplier: The combined decimal odds of a parlay. Multiply each leg's decimal odds together to get the multiplier.
Mug Bet: A small, unconventional bet placed by a matched bettor or arber to make their account look like a recreational customer's, delaying account restrictions.

N

No Action: A bet that is voided — typically due to a postponement, scratch, or rule change — with the stake returned in full.
No-Vig (No-Juice) Odds: The probability implied by a market with the bookmaker's margin removed. Used to estimate "fair" probability for value comparisons.

O

Odds: The price a sportsbook offers, expressed in American, Decimal, or Fractional format. Reflects implied probability plus the book's margin.
Odds-On: A favorite priced at less than 1/1 (Evens) — i.e. you risk more than you win. Decimal under 2.00, American negative. "Odds-on jolly" in UK racing parlance.
Off The Board (OTB): A market that's been removed by the sportsbook — usually because of injury news or other late-breaking information.
Outright: A bet on the eventual winner of a tournament or season (futures market). "Outright winner" of the Premier League, World Cup, NBA Championship, etc.
Over/Under (Total): A bet on whether the total points/goals/runs scored in a game will be over or under a posted number. The sportsbook's margin sits in the juice on each side.

P

Parlay (Accumulator): A bet combining multiple selections; all must win. Each leg's decimal odds multiply together. Bigger payouts but bigger risk. See the Parlay Calculator.
Patent: A system bet of 7 wagers across 3 selections — 3 singles, 3 doubles, 1 treble. A safer alternative to a 3-leg parlay.
Payout: The total amount returned on a winning bet, including stake. Stake × decimal odds = payout.
Pick'em (PK): A point-spread market with no favorite — both sides are 0 or pick'em. Bet on the straight winner.
Place: In horse racing, finishing in one of the paid positions short of winning (typically 2nd, 3rd, sometimes 4th). The Place portion of an Each-Way bet pays at reduced fractional terms.
Point Spread (Spread): A handicap added to one team to even the market — e.g. Patriots −7 means they must win by 8+ to cover. Common in NFL, NBA, college football, college basketball.
Prop Bet (Proposition): A bet on a specific event within a game — first scorer, total assists, longest field goal — rather than the final result.
Push: A bet that ends in a tie with the line. Stake returned, no profit, no loss. Can be eliminated by half-point lines (e.g. −7.5 instead of −7).
Punter: British slang for a bettor.

Q

Qualifying Bet: A small-loss bet placed to satisfy the wagering requirement of a free-bet promotion. Central to matched betting mechanics.
Quarter Line: An Asian Handicap or total at a quarter increment (e.g. −1.25, +0.75). The stake splits across two adjacent half-lines, producing Half Win or Half Loss outcomes. Handled automatically by the Asian Handicap Calculator.

R

Round Robin: A bet covering every parlay combination of a chosen size across a set of selections. A 3-team round robin of 2-team parlays = 3 bets.
Rule 4: UK racing rule deducting a percentage from winnings when a horse is withdrawn after odds were set. Deduction depends on the withdrawn horse's price — handled in the Each-Way Calculator.
Run Line: The MLB equivalent of a point spread, almost always set at ±1.5 runs. Tighter than NFL/NBA spreads because most baseball games are decided by 1–3 runs.

S

Same Game Parlay (SGP): A parlay built entirely from markets within one game. Books correlate the legs, so SGPs cost more juice than independent-game parlays.
Sharp: A skilled, profitable bettor whose action moves lines. Books either limit sharps quickly or use their action to set sharper lines.
Shop (Line Shopping): Comparing odds across multiple sportsbooks to take the best price on each bet. Essential for serious bettors — even a few cents per bet compound over time.
Short Price: Low odds on a heavy favorite. "Short of the price" means the actual probability is even higher than the offered price implies.
SR / SNR: Stake Returned vs Stake Not Returned. Free-bet conversion rates differ dramatically: SR free bets convert at ~95%, SNR at 70–85%. Read promo terms carefully.
Stake: The amount you bet. "Each-Way £5" means a £10 total stake (£5 Win + £5 Place).
Steam (Steam Move): A rapid, sharp line move — usually triggered by syndicate money or breaking news — that other books quickly mirror.
System Bet: A wager covering multiple combinations of selections — Trixie, Yankee, Lucky 15, Heinz, Goliath, etc. Some legs can lose and the bet still profits. Built into the Parlay Calculator.
Sweetheart Teaser: A teaser at a non-standard size (e.g. NFL 10-point) priced at much worse odds. The line moves further but math is harsher.

T

Take The Points: To bet the underdog ATS — i.e. take the +N points side of a spread. The opposite of "lay the points" (bet the favorite).
Teaser: A parlay variant where each leg's spread or total is shifted in your favor by a fixed number of points (NFL 6/6.5/7, NBA 4/4.5/5) at lower odds. See the Teaser Calculator.
Total: The sportsbook's posted points/goals/runs line for an over/under market.
Tote: Pari-mutuel betting, where stakes from all bettors form a pool and winnings are paid from the pool after a takeout. Standard in U.S. horse racing.
Treble: A 3-leg parlay (UK terminology). A "treble" of 1.50/2.00/3.00 has a multiplier of 9.0.
Trifecta: A horse-racing bet on the exact 1-2-3 finishing order. Pays substantially more than a Win bet but is much harder to hit.
Trixie: A system bet of 4 wagers across 3 selections — 3 doubles + 1 treble (no singles). One of the smaller multiple-leg bets that still pays without all selections winning.

U

Underdog: The team or player the sportsbook rates as less likely to win. Plus-money in American odds, above 2.00 in decimal. Slang: "dog" or "pup."
Unit: A standardized bet size used to compare results across bettors and bankrolls. 1 unit is typically 1% of bankroll. "He's up 50 units this season" describes profit relative to bet size.
Upset: An underdog winning outright against expectations.

V

Value: The difference between fair odds and offered odds. A "value bet" has positive expected value — the offered price is higher (longer odds) than the fair probability suggests.
Vig (Vigorish): The sportsbook's commission, baked into the prices. Same as juice. Standard NFL/NBA spread vig is around 4.5% per bet (−110 each side).
Void: A bet that the sportsbook nullifies — postponement, rule change, scratched horse, etc. Stake returned in full.

W

Wager: Synonym for bet. "Place a wager" = "place a bet."
Win Bet: In horse racing, a bet that the horse finishes 1st. The Win half of an Each-Way bet.
Wong Teaser: An NFL teaser strategy popularized by Stanford Wong: tease favorites of −7.5/−8/−8.5 down through −1.5/−2/−2.5, or underdogs of +1.5/+2/+2.5 up through +7.5/+8/+8.5. Both ranges cross key numbers 3 and 7.

Y

Yankee: A system bet of 11 wagers across 4 selections — 6 doubles + 4 trebles + 1 four-fold. A staple of UK horse racing punters.