Betting glossary

Arbitrage betting, or arbing, is placing bets on every outcome of an event at different sportsbooks whose combined prices guarantee a locked result. When one book's odds are out of step with another's, backing all sides can secure the same outcome no matter who wins.

A backdoor cover happens when late, often meaningless scoring changes which side beats the point spread, even though it does not affect who wins the game. A garbage-time score can flip a bet from a loss to a win, or the reverse, in the final moments.

A bankroll is the fixed amount of money you set aside for betting, kept separate from the money you live on. Managing it means deciding in advance how much of it any single bet can risk, so that a bad run cannot do damage beyond the limit you chose.

The bid is the highest price a buyer will currently pay; the ask is the lowest price a seller will accept. The gap between them is the spread. On an exchange that spread is the effective cost of trading, the market's own version of the margin a sportsbook builds into its odds.

Buying points means paying a worse price in exchange for shifting a point spread or total in your favor. You accept a lower payout to move the number past a safer spot, trading potential profit for a better chance of winning the bet. It rarely helps unless it crosses a key number.

Chalk is slang for the favorite in a game or market, the side most expected to win. To bet the chalk is to back the favorite. A chalky slate or parlay is one stacked with favorites, and a chalk result is when the favorites win as expected.

Closing line value, or CLV, is the difference between the odds you bet and the final odds when the market closes. If you took a better price than the closing line, you have positive CLV, a sign your bet beat where the market ultimately settled.

To cover the spread is to beat the point spread, not just win the game. A favorite covers by winning by more than the spread. An underdog covers by losing by less than the spread or by winning outright. A bet on the spread wins only if that side covers.

A dead heat is when two or more selections tie for a position that only some can fill, such as a finishing place. Rather than paying everyone in full, sportsbooks split the payout using dead-heat rules, dividing your stake by the number of tied entries and paying on that fraction.

An event contract is a tradable agreement that pays a fixed amount, often one dollar, if a stated event happens and nothing if it does not. Because the payout is fixed, its price maps directly to a probability: a contract trading at 63 cents implies the market sees about a 63 percent chance.

Exiting a position means selling a contract before the event resolves, rather than holding it to settlement. You do it to lock in a gain while the price is favorable or to cut a loss while some value remains, a choice a fixed sportsbook ticket does not give you once it is placed.

Expected value, or EV, is the average result you would expect from a bet if you could place it many times. It weighs each outcome by its probability and its payoff. A positive EV bet gains on average over the long run, a negative EV bet loses on average.

The favorite is the side a sportsbook judges more likely to win. On the moneyline it carries minus odds and pays less than an even bet, because you are trading a smaller payout for a higher chance. On the spread, the favorite is the team giving up points.

A first-half bet is a wager settled entirely on what happens in the first half of a game, ignoring the rest. Spreads, totals, and moneylines all come in first-half versions, letting you bet on a shorter window where early pace or a fast start matters most.

A flex play is a pick'em entry that still pays a reduced amount if one of your picks misses, instead of losing everything. You trade a lower top payout for partial insurance, so a near-miss on a multi-pick entry can still return some money rather than nothing at all.

A futures bet is a wager on an outcome that will be decided later in a season or tournament, such as which team wins a championship or how many games a team wins. The odds are posted well in advance and can move sharply as the event approaches.

The handle is the total amount of money wagered on an event, a market, or across a sportsbook over a period. It is a measure of betting volume, not profit. The sportsbook keeps only a fraction of the handle, called the hold, which comes from the vig built into the odds.

Hedging is placing a second bet on the opposite outcome to reduce risk on an existing wager. It can lock in a portion of a potential win or limit a possible loss, trading away some upside for a more certain result no matter how the event turns out.

The hold is the percentage of all money wagered that a sportsbook expects to keep after paying out winners. It reflects the margin, or vig, built into the odds across a market. A higher hold means the book has priced in a larger edge for itself.

Implied probability is the chance of an outcome that a set of odds represents, expressed as a percentage. Converting a price into implied probability lets you compare the sportsbook's view against your own, which is the core skill behind judging whether a bet offers value.

A key number is a final margin that games land on far more often than others, because scoring comes in fixed chunks. In many sports, spreads and totals cluster around these figures, so moving a line across one changes how often a bet wins by a meaningful amount.

A limit order is an instruction to buy or sell a contract only at a set price or better, never worse. It waits in the order book until someone takes the other side at your price, unlike a market order that fills right away at whatever price is currently available.

Liquidity is how much can be traded near the current price without pushing that price around. A market is liquid when large orders fill close to where they are quoted, and thin when even a modest order moves the price. A great quote you cannot fill at size is not really a price.

Live betting, also called in-play betting, is wagering on a game while it is happening. Odds update continuously as the score, time, and momentum change, so lines that existed before kickoff are constantly repriced. Bets are offered and pulled in seconds as the situation shifts.

A longshot is an outcome considered unlikely, carrying long odds and a large potential payout relative to the stake. Betting a longshot means backing an underdog or a rare result, accepting a low chance of winning in exchange for a bigger return if it hits.

Middling means betting both sides of a game at different numbers, so that if the final result lands in the gap between them, both bets win. If it does not, one side wins and the other loses, usually costing only the small vig on the losing ticket.

A moneyline bet is a wager on which team or player wins outright, with no point spread involved. The favorite is shown with minus odds and pays less, while the underdog is shown with plus odds and pays more. It is the simplest bet in sports.

A multiplier is the fixed factor a pick'em entry pays out, such as 6x for three correct picks. It looks like a simple reward, but every multiplier implies a required per-pick win rate to break even, and the gap between that rate and a fair coin flip is where the house edge hides.

No-vig odds are prices with the sportsbook's margin mathematically removed, so the implied probabilities of all outcomes add up to exactly 100 percent. Stripping the vig reveals the market's honest estimate of each side's chances, which is the number you can compare against your own to judge value.

Betting odds are the price of a bet. They set how much a winning bet pays and, read closely, they reveal how likely the sportsbook thinks an outcome is. Odds come in three formats: American, decimal, and fractional, each expressing the same thing in a different style.

An order book is the live, ranked list of every open buy order (bids) and sell order (asks) at each price on an exchange. It shows not just the best available prices but the depth behind them: how many contracts sit waiting at each level, revealing where real interest is.

An over/under, also called a total, is a bet on the combined score of both teams rather than on who wins. The sportsbook posts a number, and you bet whether the actual total lands over or under it. It lets you bet on the flow of a game without picking a side.

A parlay is a single bet that combines two or more selections, all of which must win for the parlay to pay. The payout is larger than the individual bets because the odds multiply together, but so does the risk: one losing leg sinks the entire bet.

A pick'em is a contest where you choose more or less on several player projections and combine them into one entry that pays a fixed multiplier if your picks are correct. Functionally it is a parlay built from player props: every pick must land for a standard entry to win.

A point spread is a handicap that levels an uneven matchup. The favorite is marked down by a number of points and the underdog is spotted the same number. The bet is then about the margin of victory rather than the winner, which is why both sides usually pay a similar price.

A projection is the number a platform posts for a player's stat, such as points, rebounds, or receiving yards, that you then bet over or under. It is the platform's line, and it can sit noticeably off the wider market's consensus, which is the first thing a careful player checks.

A prop bet, short for proposition bet, is a wager on a specific occurrence within a game rather than its final result. It can focus on a single player, a team, or an event, such as how many points a player scores or whether a team leads at halftime.

Public betting is the collective action of casual, recreational bettors, often called the public or square money. It tends to favor popular teams, favorites, and overs. Sportsbooks track it because heavy public money on one side can shape where a line settles.

A push is a tie between your bet and the sportsbook, which happens when the result lands exactly on the number. On a spread of 7, a favorite winning by exactly 7 is a push. No one wins the bet, and your original stake is returned to you in full.

Resolution rules are the written criteria that decide exactly how a contract settles: what counts as the event happening, which source is authoritative, and how edge cases are handled. On an exchange the rules are the bet itself, so reading them before you trade is basic discipline, not fine print.

Reverse line movement is when a betting line moves in the opposite direction of where most of the tickets are landing. If the majority backs one side but the number shifts toward the other, it hints that a smaller amount of sharper money is outweighing the public count.

Rollover, also called playthrough, is the total amount you must wager before a promotional bonus can be withdrawn as real cash. A bonus with a high rollover requirement forces you to bet it many times over, and the vig on each bet steadily erodes the value along the way.

A same-game parlay combines multiple bets from a single event into one wager, where every leg must hit to pay out. Because the outcomes often influence each other, sportsbooks price these correlations in, which is why the payout usually differs from stacking the same legs across separate games.

A sharp is a skilled, disciplined bettor whose wagers are respected by sportsbooks for their accuracy. Sharp money often moves lines because books adjust prices when these bettors act. The term contrasts with the public, the broader casual betting crowd.

Slippage is the difference between the price you expected to get and the price you actually got when your order filled. It is worst in thin markets, where a large order eats through several price levels. The bigger your order relative to available liquidity, the more slippage tends to cost you.

A sportsbook is the company or venue that sets odds, accepts bets, and pays out winners. Also called a book, it makes money from a margin called the vig priced into its odds rather than from any single result. Its goal is balanced action, not beating you on one bet.

Steam is a fast, heavy, and synchronized line move that sweeps across many sportsbooks at once. It usually signals a wave of money hitting the same side in a short window, forcing books to adjust their numbers together before they get caught offering a stale price.

A teaser is a type of parlay that lets you shift the point spread or total in your favor on two or more selections, in exchange for a lower payout. Every leg still has to win at the adjusted number, so the softer lines come at the cost of reduced odds.

A tout is someone who sells betting picks or predictions, often promising winning records that are hard to verify. WiserWager is not a tout and does not sell picks; it teaches you to evaluate bets yourself and to treat anyone guaranteeing profits with healthy skepticism.

The underdog is the side a sportsbook judges less likely to win. On the moneyline it carries plus odds and pays more than an even bet, rewarding the lower chance with a bigger return. On the spread, the underdog is the team receiving points as a head start.

A unit is a standard bet size, expressed as a fixed slice of your bankroll rather than a dollar amount. Most bettors set one unit at 1 to 2 percent of their bankroll. Using units keeps bet sizing consistent and lets bettors compare results without revealing exact stakes.

Variance is the natural swing of results around their long-run average. Even a well-reasoned bet can lose, and a poor one can win, over the short term. Variance describes how far and how often actual outcomes stray from what the underlying probabilities would predict.

The vig, also called the juice, is the margin a sportsbook builds into its odds. It is the reason the implied probabilities of all outcomes add up to more than 100 percent. The vig is how a book earns its money, and it is the tax every bettor quietly pays on each bet.