Sports Betting Glossary

Plain-English definitions of the terms you'll see across 1.ML and every sportsbook. Understanding these concepts is the first step to reading odds and spotting value like the models do.

Money Line
A money line is a bet on which team or player will win a game outright, with no point spread involved. Odds are shown as a positive number (the underdog, e.g. +150) or a negative number (the favorite, e.g. -180). 1.ML specializes in AI-driven money line predictions across major sports.
Point Spread
A point spread is a handicap the favorite must overcome for a bet to win. If a team is -6.5, they must win by 7 or more; the underdog at +6.5 can lose by 6 or fewer and still cover. Spreads level the playing field between mismatched teams.
Over/Under (Totals)
The over/under, or total, is the combined score of both teams in a game. Bettors predict whether the actual total will be over or under the number set by the sportsbook, independent of which team wins.
Implied Probability
Implied probability is the win chance suggested by betting odds, expressed as a percentage. For example, odds of -200 imply about a 66.7% chance. Comparing implied probability against a model’s true probability is how bettors find value.
Vig (Juice)
The vig, or juice, is the built-in commission a sportsbook charges on a bet. It is why the implied probabilities of both sides of a market add up to more than 100%. Removing the vig reveals the book’s true assessment of each outcome.
No-Vig Line
A no-vig (or fair) line is the odds after the sportsbook’s commission is mathematically removed, so both sides sum to exactly 100%. It represents the market’s genuine estimate of each outcome and is a key input for spotting value.
Closing Line Value (CLV)
Closing line value measures whether you bet at better odds than the final (closing) line before kickoff. Consistently beating the closing line is the strongest statistical indicator of long-term betting skill.
Parlay
A parlay combines multiple bets into one wager. Every selection, or leg, must win for the parlay to pay out. Parlays offer larger payouts because the combined probability is lower and the risk is higher.
Player Prop
A player prop is a bet on an individual player’s statistical performance — such as points, rebounds, passing yards, or strikeouts — rather than the final result of the game.
Expected Value (EV)
Expected value is the average amount a bet is projected to win or lose if it were placed many times. A positive-EV (+EV) bet is one where your estimated win probability is higher than the odds imply — the mathematical foundation of profitable betting.
Kelly Criterion
The Kelly Criterion is a formula that calculates the optimal fraction of a bankroll to stake on a bet, based on your edge and the odds. It maximizes long-term growth while controlling risk of ruin. Many bettors use a fractional (e.g. half-Kelly) version.
Handle
Handle is the total amount of money wagered on an event or over a period of time. It is a measure of betting volume, not profit, and is often used to gauge the popularity of a market.