Sports betting glossary
Every term you'll meet on a betting board, defined without jargon. One term, one page — link straight to any of them.
54 terms
A
- American odds
- — The +/− format used in the US, showing profit on a $100 stake or the stake needed to win $100.
- Arbitrage
- — Betting both sides at different books at prices that guarantee a profit whatever happens.
B
- Bankroll
- — The money set aside specifically for betting, separate from everything else you own.
- Breakeven win rate
- — The percentage of bets you must win at a given price just to avoid losing money.
C
- Closing line
- — The final price on a market immediately before the event starts.
- Closing line value
- — Whether the price you got was better than the price the market settled at by game time.
- Confidence score
- — How much data sits behind a grade — sample depth, book coverage and consistency, on a 0 to 1 scale.
- Correlation
- — The degree to which two betting outcomes move together — the thing that makes some parlays worth building.
- Cover
- — Beating the point spread, as opposed to simply winning the game.
D
- Decimal odds
- — Odds expressed as the total return per unit staked, including the stake itself.
E
- Edge
- — The gap between your estimated probability and the probability the price implies. Positive means value.
- Expected value
- — The average result of a bet per unit staked if it could be repeated indefinitely.
F
- Fair probability
- — The market's honest opinion — implied probability with the bookmaker's margin removed.
- Favorite
- — The side expected to win, priced with negative odds or laying points.
- Flat betting
- — Staking the same amount on every bet regardless of how good it looks.
- Free bet
- — A promotional wager that pays only the profit, not the stake, if it wins.
H
I
- Implied probability
- — The chance of an outcome as expressed by its odds, including the bookmaker's margin.
K
- Kelly criterion
- — A staking formula that sizes each bet to the size of its edge, maximising long-run bankroll growth.
- Key numbers
- — The margins that occur far more often than others, mainly 3 and 7 in football.
L
- Limit
- — The maximum a sportsbook will accept on a market — or on you specifically.
- Line
- — The number a sportsbook posts on a market — a spread, a total, or a price.
- Line shopping
- — Checking multiple sportsbooks for the same bet and taking the best available price.
M
- Middle
- — Betting both sides at different numbers so that certain results win both bets.
- Model probability
- — WeBall's own estimate of how often a bet wins, before comparing it to any price.
- Moneyline
- — A bet on which side wins outright, with no spread involved.
N
- No-vig odds
- — Odds with the bookmaker's margin normalised out, showing what the market actually believes.
O
- Odds boost
- — A promotion that improves the price on a specific bet above its normal number.
- Opening line
- — The first price a sportsbook posts on a market, before it takes meaningful action.
P
- Parlay
- — A single bet combining several selections, all of which must win to pay out.
- Point spread
- — A margin handicap that makes an uneven matchup close to a coin flip.
- Prop bet
- — A bet on something other than the final result — usually an individual player's statistical total.
- Push
- — A tie against the number — the bet is void and your stake is returned.
R
- Regression to the mean
- — The tendency of extreme performances to be followed by more ordinary ones.
- Reverse line movement
- — A line moving toward the side receiving fewer bets — a classic sign of sharp money.
- Risk of ruin
- — The probability of losing your entire bankroll before your edge has time to show.
S
- Same-game parlay
- — A parlay whose legs all come from one game, priced to account for how they relate to each other.
- Sample size
- — How many observations sit behind a number — and whether it means anything yet.
- Sharp
- — A consistently profitable bettor, or the money such bettors move a line with.
- Slate
- — Every game and market currently available to bet across all covered sports.
- Square
- — A casual bettor, and by extension the predictable side of the market they bet.
- Steam
- — A fast, uniform line move across many sportsbooks at once, driven by heavy informed money.
T
- Teaser
- — A parlay where you move each spread or total in your favour in exchange for a shorter payout.
- The board
- — WeBall's home canvas — a generative workspace that composes itself around the games and edges you're looking at.
- Tilt
- — Betting emotionally after losses — chasing, staking up, and abandoning your process.
- Total
- — A bet on whether combined scoring finishes above or below a set number.
U
V
- Value bet
- — A bet whose price is better than the true probability of the outcome.
- Variance
- — The spread of outcomes around your expected result — why good bettors have terrible months.
- Verdict
- — WeBall's grade for a single bet — how the model's probability compares to the best available price.
- Vig
- — The bookmaker's built-in margin — the reason both sides of a market add up to more than 100%.