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The words, defined.
Plain definitions of the betting terms Unitley and its guides use, each with an example where one helps and a link to the guide or calculator that goes further.
A
- Alternate line
A spread or total at a different number from the main line, priced to match: more points at a shorter price, fewer points at a longer one. The sportsbook's margin is built in again.
ExampleWith a team favored by 6.5 at −110, an alternate −3.5 costs a shorter price than −110, and an alternate −9.5 pays a longer one.
- American odds
The US way of writing a price. A minus price is the stake that wins $100; a plus price is what a $100 stake wins. Even money is +100.
ExampleAt −150 you stake $150 to win $100. At +130, $100 wins $130.
- Anytime touchdown
A player prop that wins if the player scores a touchdown at any point in the game. It is usually priced one way only, with no “no” side to compare against, so the margin is harder to see.
ExampleAt +120, $100 on a player to score anytime wins $120 if they score once or more.
In UnitleyUnitley covers anytime touchdowns for NFL games, alongside passing, rushing and receiving yards.
B
- Bankroll
Money set aside for betting and nothing else: an amount you can afford to lose. Stakes, units and loss limits are all sized from it, so it should be a real, separate amount.
In UnitleyYour bankroll in Unitley is your starting amount plus the profit or loss of every settled bet.
- Break-even chance
The win rate a price needs just to stay level over time. It is the price's implied probability, with the sportsbook's margin included.
ExampleAt −110 you need to win 52.38% of your bets to break even, not 50%.
C
- Closing line valueAlso CLV
How much better your price was than the closing line, the market's last price before the game starts. It is measured in implied probability, fairest against the closing no-vig chance. One bet's CLV says little; a long record of it says a lot.
ExampleYou bet a side at +150 (40.00%) and it closes at +130 (43.48%): about 3.5 points of CLV.
- Consensus
A price or chance built from several sportsbooks rather than one. A no-vig consensus is a stronger estimate of an outcome's fair chance than any single book's.
In UnitleyUnitley's odds show a no-vig consensus across the sportsbooks it tracks, and the expected value of FanDuel's price against it.
- Correlation
When one bet's result makes another more or less likely. Legs on the same game often are, so multiplying their chances misstates a parlay's real chance.
ExampleA favorite covering and the game going over often go together: a blowout usually means plenty of points.
- Cover
To win a bet against the spread.
ExampleA −3.5 favorite covers by winning by 4 or more. The +3.5 underdog covers by losing by 3 or fewer, or by winning.
D
- Decimal odds
The total paid back per $1 staked, stake included. The chance a decimal price implies is 1 ÷ the price.
Example2.50 returns $2.50 for each $1 staked: $1.50 profit, at a 40% implied chance.
E
- Edge
Your estimate of an outcome's chance minus the market's, in percentage points. Against the price's implied probability it says whether a bet has positive expected value; against the no-vig chance, how far you disagree with the market.
ExampleAt −220 the price implies 68.75%. Rating the side at 72% is a 3.25-point edge.
- Expected valueAlso EV
What a bet wins or loses on average if your win chance is right: the win chance times the profit, less the lose chance times the stake. It is an estimate, only as good as the chance behind it.
ExampleAt 63% and −150, a $100 bet has an EV of 0.63 × $66.67 − 0.37 × $100 = +$5.00. It still loses 37% of the time.
F
- Favorite
The side the market expects to win. It carries a minus moneyline price, or gives points on the spread.
ExampleAt −180 the favorite needs a $180 stake to win $100, and the price implies 64.29%.
- Fractional Kelly
Staking a set fraction of the full Kelly stake. It gives up a little growth for much smaller swings and much more room for error in your win chance.
In UnitleyUnitley never uses full Kelly. Its risk profiles use quarter, third or half Kelly, capped at 2%, 3% or 5% of the bankroll on any one bet.
- Fractional odds
The UK way of writing a price: the profit per unit staked.
Example3/2 pays $3 profit for every $2 staked, the same as 2.50 decimal or +150. 10/11 is −110.
- Futures
Bets settled later in the season, such as a team to win the Super Bowl or a player to win an award. The stake is tied up until the market settles.
In UnitleyFutures are coming soon in Unitley.
H
- Hold
The share of everything staked in a market that a sportsbook expects to keep if it takes balanced money on every side. It comes from the overround.
ExampleAt −110 on both sides, the hold is about 4.55%.
- Hook
The half point on a spread or total, as in “three and a hook” for 3.5. A line with a hook cannot push.
ExampleGetting +3.5 instead of +3 turns a 3-point loss from a push into a win.
I
- Implied probability
The chance a price implies: the win rate at which a bet at that price breaks even. A market's implied probabilities add up to more than 100%; the excess is the sportsbook's margin.
Example−150 implies 60.00%. +130 implies 43.48%.
K
- Kelly criterion
A formula that sizes a stake to the edge: f = (b × p − q) ÷ b, where b is the profit per $1 staked, p your win chance and q = 1 − p. Full Kelly assumes your win chance is exactly right, which it never is.
ExampleAt 55% and +100, full Kelly is 10% of the bankroll. Quarter Kelly is 2.5%.
- Key numbers
The final margins NFL games land on most often: 3 and 7 above all, since scoring comes in field goals and touchdowns. A half point across a key number is worth far more than one elsewhere.
ExampleMoving a favorite from −3 to −2.5 turns every 3-point win from a push into a win.
L
- Line
The number in a spread or total market, as opposed to its price.
ExampleIn “−3.5 at −110”, −3.5 is the line and −110 is the price.
- Line movement
How a market's line and prices change between opening and kickoff, as news and money arrive. In the NFL, injury news and forecasts move lines during the week, and the last moves come on game day.
In UnitleyUnitley shows how FanDuel's line and price have moved in each game's markets.
- Line shopping
Comparing the same bet across sportsbooks to get the best price. A better price on the same bet is value before the line moves at all.
In UnitleyUnitley shows the best price at the same line across the sportsbooks it tracks.
- Live bettingAlso In-game betting
Betting on a game while it is being played, at prices that change with the action.
In UnitleyLive betting is coming soon in Unitley. Today it covers the markets before kickoff.
- Loss limit
The most you are willing to lose in a set window, such as a day or a week, decided before you start.
In UnitleyYou can set daily and weekly loss limits. Unitley's stake suggestions stay within the room left under them, and it warns when a bet you log goes past one.
M
- Moneyline
A bet on who wins the game outright, with no points given or taken.
ExampleWith the favorite at −180 and the underdog at +155, $100 on the underdog wins $155.
N
- No-vig priceAlso Fair odds, Fair price
A price with the sportsbook's margin taken out: the market's own estimate of each outcome's chance. It is an estimate too, and the method used to remove the margin changes it a little.
ExampleFor −150 and +130, taking the margin out evenly gives fair chances of 57.98% and 42.02%: about −138 and +138.
O
- Opening line
The first line and price a sportsbook posts for a market. NFL lines for the next week are usually up by Sunday night.
- Overround
How far a market's implied probabilities add up past 100%. The smaller it is, the less every bet in that market costs.
Example−110 on both sides: 52.38% + 52.38% = 104.76%, an overround of 4.76%.
P
- Parlay
One bet made of several legs, every one of which has to win. The legs' decimal odds multiply, and so do their margins.
ExampleThree legs at 1.91, 2.10 and 1.80 make 7.22, or +622: a 13.85% implied chance.
- Player prop
A bet on one player's game rather than the result, such as their yards over or under a line.
In UnitleyFor NFL games, Unitley covers passing, rushing and receiving yards and anytime touchdowns.
- Point spreadAlso Spread
A handicap that evens out a game: the favorite gives points, the underdog gets them, and the bet is graded on the score after the points are applied.
ExampleWith the favorite at −3.5 and the underdog at +3.5, the favorite has to win by 4 or more.
- Push
A bet that lands exactly on the line. Neither side wins, and the stakes come back.
ExampleA 3-point win against −3, or 44 points between the teams against a total of 44.
R
- ROIAlso Return on investment
Profit as a share of everything staked.
Example$50 profit on $1,000 staked across all your bets is a 5% ROI.
In UnitleyUnitley's Bet Log shows your record, ROI and units won.
S
- Same-game parlayAlso SGP
A parlay whose legs all come from one game. The legs are usually correlated, so sportsbooks price them together, often with a bigger margin than the legs carry on their own.
In UnitleyUnitley's Parlay Builder warns when legs share a game, since their combined chance is then unreliable.
- Stake cap
The most any one bet may be, as a share of the bankroll or in dollars.
In UnitleyUnitley's risk profiles cap one stake at 2%, 3% or 5% of the bankroll, and you can set a dollar maximum on top.
- Steam
A sudden line move across many sportsbooks at once, usually from heavy money on one side.
T
- TotalAlso Over/under
A bet on the combined score of both teams, over or under a number the sportsbook sets.
ExampleAt 44.5, the over wins if the teams score 45 or more between them, the under at 44 or fewer.
U
- Underdog
The side the market expects to lose. It carries a plus moneyline price, or gets points on the spread.
ExampleAt +155, $100 wins $155, and the price implies 39.22%.
- Unit
A standard stake, often 1% to 2% of the bankroll. A record kept in units compares across bankroll sizes.
Example+12 units means the same at a $500 bankroll as at $50,000.
In UnitleyIn Unitley a unit is a flat amount or a share of your bankroll, your choice, and results show in units.
V
- VigAlso Juice, Margin
The sportsbook's margin, built into its prices. It is why both sides at −110 imply more than 100% between them, and why a bettor laying −110 has to win more than half the time.
Missing a term? The guides go further on each of these, and the FAQ covers Unitley itself.
Put the math to work.
Unitley shows the no-vig price and expected value for every NFL game it covers, and sizes stakes to your own bankroll: in your own Claude, in another AI agent, or in the web app on your own key. Analysis, never a guarantee.