Reference
SPORTS BETTING
GLOSSARY

Plain-English definitions of every term you'll see on this site and at the sportsbook. No jargon, no assumed knowledge.

Moneyline (ML)
Also called: straight-up, ML
The simplest bet in sports — you pick which team wins, period. No spread involved. The odds reflect how likely each team is to win: favorites pay less, underdogs pay more.
Yankees -180 vs Red Sox +155
Bet $180 on the Yankees to win $100. Bet $100 on the Red Sox to win $155.
ATS (Against the Spread)
Also called: spread, run line (MLB), puck line (NHL), point spread
Instead of picking who wins, you pick whether a team wins by more than a set number of points/runs (covers the spread) or keeps the game close enough (beats the spread as the underdog). In baseball the spread is always ±1.5 runs. In basketball it varies by game.
Dodgers -1.5 vs Padres +1.5
Dodgers must win by 2+ runs to cover. Padres cover if they win OR lose by exactly 1.
Run Line
Baseball term for ATS
Baseball's version of the point spread. Always set at ±1.5 runs. The favorite is -1.5 (must win by 2+), the underdog is +1.5 (covers if they win or lose by 1). Same concept as ATS — just baseball's specific name for it.
Cubs -1.5 (-120) vs Brewers +1.5 (+100)
Cubs must win by 2+ runs. Brewers cover if they lose by 1 or win outright.
Spread
Also called: point spread, line
The number of points a favorite must win by for a bet on them to pay out. Set by sportsbooks to attract equal money on both sides. A negative spread means the team is favored; positive means they're the underdog.
Thunder -8.5 vs Timberwolves +8.5
Thunder must win by 9+ points. Timberwolves cover if they win or lose by 8 or fewer.
Cover
Also called: cover the spread
When a team wins their ATS bet. The favorite "covers" by winning by more than the spread. The underdog "covers" by winning outright or losing by less than the spread.
Juice / Vig
Also called: vigorish, the cut, commission
The sportsbook's built-in fee. Standard juice is -110 on both sides of a spread, meaning you bet $110 to win $100. The 10% difference is how the book makes money regardless of who wins.
Both teams listed at -110
You need to win 52.4% of bets just to break even after juice.
Over / Under (O/U)
Also called: total, game total
A bet on whether the combined score of both teams will be over or under a number set by the sportsbook. You're not picking a winner — just whether it'll be a high- or low-scoring game.
Total set at 8.5 (Cubs vs Brewers)
Over wins if the combined runs scored is 9 or more. Under wins at 8 or fewer.
Implied Probability
Also called: implied odds, market probability
The win probability baked into the Vegas odds. A -180 moneyline implies a 64.3% chance of winning. Our model compares its own probability to this number to find edges.
-180 → implied probability = 180 / (180 + 100) = 64.3%
+155 → implied probability = 100 / (155 + 100) = 39.2%
Confidence Tier
How we grade our own picks
Our internal grading system based on how strongly our AI models agree. When multiple models independently point to the same team, confidence is higher. Three tiers: Lean (50–67%), Med (67–70%), and High (70%+). High confidence picks have historically won at the highest rate.
ROI (Return on Investment)
Also called: return, profit percentage
Profit as a percentage of total wagered. An ROI of +5.5% means for every $100 bet, you averaged $5.50 profit over the sample. Accounts for juice, so a positive ROI is meaningful — you need to win ~52.4% just to break even.
Unit (u)
Also called: flat bet
A standardized bet size used to measure profit without tying it to a dollar amount. One unit = whatever your standard bet is ($10, $50, $100). Tracking in units keeps results honest and comparable regardless of bet size.
Split Pick
Site-specific term
When our moneyline model and ATS model disagree on which team to back. For example: our model picks the Padres to win the game (moneyline), but the Dodgers to cover -1.5 (ATS). Both picks are shown — you choose which market to play.