Sports betting glossary: every term in plain English
Every term on vigged in a sentence or two, from ATS to void. Where a term needs more than that, it links the guide or calculator that goes deeper.
- Against the spread (ATS)
- A team’s record or a bet’s result counted with the point spread applied, not straight up. A favorite can win the game and still lose ATS.
- Alternate line
- A spread or total other than the main one, at a different price: more points cost more, fewer points pay more.
- American odds
- The US price format. A minus price (−150) is what you stake to win $100; a plus price (+150) is what a $100 stake wins. How to read American odds →
- Arbitrage (arb)
- Backing every outcome at different books whose prices together imply less than 100%, so the return is the same whatever happens. Small, short-lived and full of practical risks. Arbitrage betting explained →
- Asian handicap
- A soccer handicap with no draw: half lines (−0.5) settle win or lose, whole lines (0, −1) can push, and quarter lines (−0.25, −0.75) split the stake across two lines. Asian handicap explained →
- Bankroll
- The money you set aside for betting and nothing else. Bet sizes are best set as a share of it, and it should be money you can afford to lose. Bankroll and variance →
- Break-even win rate
- How often a bet at a given price has to win to make no money over time. It is the price’s implied probability: 52.4% at −110. Implied probability →
- Buying points
- Taking a better spread or total than the main one for a worse price, such as −2.5 at −125 instead of −3 at −110. Worth it only when the price is right, most often across a key number. Half point calculator →
- Chalk
- The favorite, or betting on favorites. A chalky slate is one where the favorites mostly won.
- Closing line
- The last price before a game starts. With the most information behind it, it is usually the market’s sharpest estimate. Closing line value (CLV) →
- Closing line value (CLV)
- How much better the price you took was than the closing price. Beating the close regularly is the best evidence a bettor has of an edge. Closing line value (CLV) →
- Cover
- To beat the point spread. A −6.5 favorite covers by winning by 7 or more; a +6.5 underdog covers by losing by 6 or fewer, or winning.
- De-vig
- Removing the book’s margin from a set of prices to estimate no-vig probabilities. Methods differ in how they share the margin between favorite and underdog. What are no-vig odds →
- Decimal odds
- The total returned per 1 staked, stake included: 2.50 returns 2.50 for 1 (1.50 profit). Common outside the US. Odds converter →
- Draw no bet
- A soccer bet on one team where a draw refunds the stake. The same as an Asian handicap of 0. Draw no bet →
- Event contract
- A prediction-market contract, such as on Kalshi or Polymarket, that pays $1 if an outcome happens. Its price in cents reads as a probability. Kalshi sports odds →
- Expected value (EV)
- What a bet returns on average if it could be repeated many times: win probability times profit, minus loss probability times stake. Positive EV means the price pays more than the bet is worth. How to find +EV bets →
- Favorite
- The side the market expects to win: a minus moneyline, or the side giving points on a spread.
- Favorite-longshot bias
- Longshots winning less often than their prices imply, so books load more of the margin onto them. Strong at sharp books such as Pinnacle; on US-league moneylines at retail books the data showed the opposite tilt. De-vig methods: the evidence →
- Fractional odds
- The UK format: profit over stake. 5/2 wins 5 for every 2 staked, the same as +250. Odds converter →
- Futures
- Bets on an outcome settled later in a season, such as a champion or an award. Prices usually carry much more margin than single games.
- Handle
- The total amount bet on a game, a market or at a book.
- Hedge
- A bet against a position you already hold, to take some profit off the table or cut a possible loss. Hedge calculator →
- Hold
- The book’s margin on a market: how far its implied probabilities add up above 100%. About 4.8% on −110 both ways. What are no-vig odds →
- Implied probability
- The win chance a price implies, before removing the margin: 100 / (odds + 100) for plus prices, |odds| / (|odds| + 100) for minus prices. Implied probability →
- Juice
- Another word for the vig: the margin built into a book’s prices. What are no-vig odds →
- Kelly criterion
- A staking rule that sizes a bet by your edge and the price. Full Kelly swings hard, so most people who use it bet a half or a quarter. Kelly criterion calculator →
- Key number
- A margin of victory that comes up unusually often, like 3 and 7 in the NFL. Half a point through a key number is worth much more than elsewhere. Half point calculator →
- Limit
- The most a book will accept on a bet. Limits are low when a line first opens and rise as the market firms up. Why odds move →
- Line
- The number on a spread or total (−3.5, 44.5), and loosely the price of any bet.
- Line movement
- A change in a line or price after it opens, from news, bets the book respects, or other books moving. Why odds move →
- Line shopping
- Comparing books and taking the best number for the bet you already want. The simplest edge in betting. Line shopping →
- Live betting
- Betting after a game has started, at prices that move with every play. Also called in-play.
- Market maker
- A book that sets its own prices and takes big bets to learn from them, rather than copying other books. Why odds move →
- Middle
- Bets on both sides of a spread or total at two different numbers. A result in the gap wins both; anything else costs a little vig. What is a middle →
- Moneyline
- A bet on who wins the game, with no point spread. How to read American odds →
- No-vig price
- The price with the margin removed: what a line would be if the book took no margin, and the market’s best estimate of what a bet is truly worth. Also called no-vig odds. No-vig calculator →
- Off the board
- A game or market a book has stopped taking bets on, often while it waits on injury news.
- Opening line
- The first price posted on a game. Openers carry the least information and the lowest limits, so they move the most. Why odds move →
- Over/under
- A bet on whether the combined score goes over or under a number: the total.
- Overround
- The sum of a market’s implied probabilities above 100%: another name for the hold. Implied probability →
- Parlay
- One bet that combines several legs; every leg has to win. The prices multiply, and so does the margin. Parlay calculator →
- Player prop
- A bet on one player’s numbers, such as points, yards or strikeouts, rather than the game result.
- Power method
- A de-vig method that raises each implied probability to the same power so they sum to 100%. It takes more of the margin off the longshot than multiplicative or additive, and scored best on sharp moneylines and soccer 1X2. De-vig methods: the evidence →
- Puck line
- The NHL’s point spread, almost always 1.5 goals. Baseball’s version is the run line.
- Push
- A tie with the line, such as a 3-point win on −3. The stake comes back.
- Reverse line movement
- A line moving toward the side with fewer bets. Usually fewer, bigger bets on that side explain it; a move against both bets and money points to bettors the book respects, news or another book. Why odds move →
- Sharp
- A bettor, or a book, whose prices and bets tend to beat the closing line. The opposite of square.
- Shin method
- A de-vig method built on a model of a few bettors knowing more than the book. In a two-way market it gives exactly the same no-vig prices as additive: the same number of points off each side. De-vig methods: the evidence →
- Spread
- Points given to the underdog to even up a game. The favorite has to win by more than the spread to cover.
- Square
- A recreational bettor, or a bet the public likes. Not an insult, just the other side of sharp.
- Stake
- The amount you put on a bet. If the bet loses, the stake is what you lose.
- Steam
- A fast, market-wide line move, usually after big bets from respected bettors hit several books at once. Why odds move →
- Three-way moneyline (1X2)
- A soccer result bet with three outcomes: home win (1), draw (X), away win (2). Three-way moneyline and the draw →
- Total
- The combined-score line in an over/under bet.
- Underdog
- The side the market expects to lose: a plus moneyline, or the side getting points on a spread. Often just the dog.
- Unit
- A standard bet size, usually 1% to 2% of a bankroll, so results compare across bettors and bankrolls. Bankroll and variance →
- Variance
- How far real results swing around what is expected. Over a few hundred bets it can hide a real edge, or make a losing bettor look like a winner. Bankroll and variance →
- Vig
- The margin a book builds into its prices: the reason both sides of a coin flip are −110, not +100. Short for vigorish; also called juice. What are no-vig odds →
- Void
- A bet canceled by the book, such as when a game is not played or a player does not start. The stake is returned.
Frequently asked questions
What is the vig in sports betting?
The vig, or juice, is the margin a sportsbook builds into its prices. It is why both sides of an even game are priced at −110 rather than +100: the book takes in more than it pays out whichever side wins.
What does −110 mean?
You stake $110 to win $100. If the bet wins you get $210 back, your $110 stake plus $100 profit. It implies a 52.4% chance, which is the win rate a −110 bet needs to break even.
What is the difference between a sharp and a square?
A sharp is a bettor whose bets tend to beat the closing line, so books respect their action and often move on it. A square is a recreational bettor. Books set limits and move lines differently for each.
What is a unit in betting?
A unit is a standard bet size, usually 1% to 2% of a bankroll. Talking in units instead of dollars makes results comparable between bettors with different bankrolls.
Live odds boards: NFL odds · NCAAF odds · NBA odds · NCAAB odds · NHL odds · MLB odds · WNBA odds · MMA odds · Cricket odds · EPL odds · MLS odds · UCL odds · Liga MX odds · La Liga odds · Serie A odds · Bundesliga odds · Ligue 1 odds · ATP odds · WTA odds
21+ | Gambling problem? Call 1-800-GAMBLER. Nothing here is betting advice, and no bet or strategy guarantees a profit. Sports betting is legal only in some US states; check the rules where you are. Responsible gambling.