Gambling glossary

Casino vocabulary is mostly plain once someone explains it, and it is rarely explained. This glossary covers the terms that carry real money consequences rather than the ones that just sound technical.

Where an entry quotes a figure, it comes from the computed sections of this site and links to the page where it is derived. A definition and its arithmetic should not live in different places.

Odds & money

• Bankroll: The money set aside for gambling, kept separate from money needed for anything else. Its right size depends more on variance than on the edge: a player chasing 35:1 payouts needs many times the bankroll of an even-money bettor to ride out a normal losing run. Decide it before you sit down. Progression systems sold as bankroll management concentrate the risk instead (see martingale).
• Expected value: The average result of a bet if it could be repeated indefinitely.
• Flat betting: Wagering the same amount every hand regardless of what came before. Each bet is independent, so sizing it by the last result cannot change the edge on any dollar bet, only the risk, and with a fixed unit the expected cost of a session is plain arithmetic: the total wagered times the house edge.
• Free odds: The bet placed behind a pass line wager once a point is set. It pays true odds, so the casino keeps nothing on it, and it is the only bet on the floor that can say that.
• House edge: The average share of each bet the casino expects to keep over the long run.
• Insurance: The side bet offered when the dealer shows an ace. Every source calls it a bad bet; this one gives the figure, and it changes with the number of decks.
• Martingale: Doubling after every loss until a win recovers everything, plus one unit.
• RTP: Return to player: the mirror of house edge, quoted as what comes back rather than what is kept.
• Standard deviation: The typical size of a swing around the expected result, in the same units as the bet. The expected loss grows with the number of bets and the typical swing only with its square root, so four times as many bets quadruple the expected loss and merely double a normal swing. See variance.
• True odds: The payout that would make a bet exactly fair, with no advantage to either side.
• Unit: One standard bet, used as the yardstick for measuring results and bankroll. Results kept in units compare across stakes: forty units up is a good session whether the unit was $5 or $500. Keeping the unit the same every hand is flat betting.
• Variance: How widely results scatter around their expected value.
• Vigorish: The built-in charge a house takes, whether as a commission, a shaded payout, or a rake.

Casino floor

• Cage: The secure counter where chips are exchanged for money; it also handles markers, cheque cashing and large transactions. In the United States cash transactions above $10,000 are reported to the authorities, and splitting them to stay under that line is an offence in itself. Chips are generally redeemable only at the property that issued them.
• Chip: The casino's own token, standing in for money at the table. In the United States the usual colours are white or blue for $1, red for $5, green for $25, black for $100 and purple for $500, a convention rather than a rule. Roulette tables give each player a colour of their own with no value printed on it, worth nothing away from that table.
• Colour up: Exchanging a pile of small chips for fewer larger ones before leaving the table. The dealer counts the stack and swaps it: the game needs its low-value chips in circulation, and a coloured-up stack is easier to count at the cage.
• Come-out roll: The first roll of a craps round, before a point exists. It settles a pass line bet at once 33.33% of the time and sets a point the other 66.67%.
• Commission: A percentage charged on winning bets that would otherwise favour the player.
• Comp: Complimentary goods or services given to players based on tracked play. Comps are figured from theoretical loss, not from what you actually lost: average bet times hours times decisions an hour times the house edge, with a share of that returned as rooms, food or credit. Winning does not reduce them, and a higher-edge game earns them faster. The figure worth asking a host for is the reinvestment rate, the share of theoretical loss that comes back.
• Cut card: A coloured plastic card placed in the shoe to mark where dealing stops: when it appears, the round finishes and the shoe is reshuffled. Where it sits sets the penetration. It is a defence against card counting and does not change a basic-strategy player's decisions.
• Drop: The money exchanged for chips at a table: the cash counted from the locked box beneath it, plus any credit drawn there. Drop measures money brought to the game, not money bet; hold is the share of it the table keeps, which is why hold runs far above the house edge (house edge against hold).
• Even money: A 1:1 payout taken on a natural against a dealer ace, instead of waiting for 3:2. On six decks it gives up 3.88% of the bet, and it is insurance under another name.
• Eye in the sky: The casino's surveillance system, and the department that runs it. Cameras cover every table, cage window and count room, and much of the department's work is watching staff rather than players. If a payout looks wrong, say so at once at the table: the recording settles most disputes, and it is easiest to find before the chips have moved.
• Handle: The total amount wagered, counting every bet including money won and bet again. The house edge applies to handle, not to the money brought to the table: a $200 buy-in bet over twenty times is $4,000 of handle. That is why a fast game at a low edge can cost more an hour than a slow one at a high edge (house edge against hold).
• High roller: A player whose stakes justify individual attention from the casino; there is no fixed threshold. The hosts, private rooms and comps are paid for out of the player's theoretical loss. High-limit rooms often deal better rules, such as single-zero roulette and 3:2 blackjack, so a higher minimum can buy a lower edge.
• Hold: The share of buy-ins a casino keeps, which is not the same as the house edge.
• Hole card: A card dealt face down and seen only by its holder. In blackjack it is the dealer's hidden card; in hold'em it is the two cards that make your hand yours.
• Marker: A line of credit extended by the casino, drawn at the table. It is a short-term loan against your bank account with a repayment date, and it is enforceable: in several jurisdictions an unpaid marker is treated as a bad cheque rather than an ordinary debt. Playing on credit removes the stopping point that running out of chips provides (responsible gaming).
• Natural: A hand that wins immediately on the first cards dealt.
• Penetration: The proportion of a shoe dealt before the reshuffle, set by where the cut card goes: at 75%, three quarters of the cards are dealt. Deeper penetration helps a card counter and does not change the decisions of anyone playing basic strategy; a continuous shuffling machine removes it entirely.
• Pit boss: The supervisor responsible for a group of tables. The pit boss resolves disputes, approves ratings, comps and limit changes, and watches for counting, past posting and dealer error.
• Punto banco: The fixed-rules form of baccarat dealt in most European and casino resorts, where no player decision exists at all.
• Push: A tie in which the bet neither wins nor loses and the stake is returned.
• Qualify: The hand a dealer needs before every bet is settled against it. In Three Card Poker the dealer misses it on 30.41% of hands; in Ultimate Texas Hold'em on 17.41%.
• Rating: The casino's record of your average bet and time played, logged by a floor supervisor against a player account. Comps, credit lines and offers all run off it. Ratings are estimates and tend to be conservative, and handing over the card at the start of a session rather than the end usually improves the record.
• Shoe: The box holding several shuffled decks from which cards are dealt.
• Soft 17: A hand of 17 counting an ace as eleven. Whether the dealer stands or hits on it is printed on the table, and it is worth 0.22 percentage points.
• State monopoly: A system where the government itself runs the gambling rather than licensing companies to do it, common across the Nordics. Norway has no casinos at all; Finland runs everything on the mainland through one company and has a single casino, in Helsinki (the Åland Islands have their own operator); Sweden's state operator closed its last casino in 2025, and casinos were abolished from 1 January 2026. Denmark, with licensed casinos since 1990, is the regional exception.
• Surrender: Folding a bad hand for half your stake. It is the one blackjack rule on this list that moves the edge in the player's direction, and most tables do not offer it.
• Table etiquette: The unwritten rules of behaviour at a casino table, most of them practical. Put cash on the felt rather than in the dealer's hand, leave your bet alone once betting is closed, and in blackjack use hand signals, which are what the cameras record. Craps has its own: roll with one hand and hit the back wall.
• Theoretical loss: What the casino expects to win from a player, used to set comps and credit.
• Toke: A tip to a dealer, often made as a bet placed on their behalf. A chip handed over is a straight tip; a bet placed "for the dealers" rides with your result. At many US tables tokes are pooled and are a real part of a dealer's income, so count them in the cost of an hour. Our tipping guide covers cash games and tournaments.
• Upcard: The dealer's one face-up card. It is the only thing you know about the dealer's hand, and it moves the dealer's bust chance from 16.65% to 42.32%.

Poker

• Ante: A small forced bet from every player, used alongside or instead of blinds. Antes enlarge the pot before anyone acts, which makes stealing it more profitable and loosens the game; tournaments add them at later levels for that reason, now usually as a single big blind ante posted by one player for the whole table.
• Blind: A forced bet posted before the cards are dealt.
• Button: The dealer position, which acts last on every postflop street. It moves one seat clockwise each hand and is the most profitable seat at the table, because acting last means acting with the most information (see position).
• Combinatorics: Counting the exact number of card combinations that make up a range.
• Cutoff: The seat immediately to the right of the button, named for cutting off the button's chance to act last: a raise from the cutoff often folds the button out. It is the second-best seat, played a little tighter than the button because the button, and before the flop the blinds, still act after it.
• Equity: Your share of the pot, meaning how often you win it if the hand plays to showdown.
• Fold equity: The value that comes from an opponent folding, separate from winning at showdown.
• Implied odds: The money you expect to win later if your draw comes in, beyond what is in the pot now.
• Outs: The cards remaining that would improve your hand to a likely winner.
• Position: Where you act in the betting order, and the largest structural edge in poker.
• Pot odds: The price a call is getting, compared against how often it needs to win.
• Rake: The house's cut of each pot, or the fee on a tournament entry.
• Range: The full set of hands a player could hold, rather than a guess at one specific hand.
• Straddle: A voluntary blind raise posted before the cards, usually double the big blind and usually from under the gun. It buys the right to act last before the flop and doubles the stakes of the hand; on its own it is almost always a losing play, because it puts money in blind from a bad seat.
• Tilt: Playing worse than you can because of emotion rather than judgement: too many hands, too many calls, bets too large. A good run causes it as well as a bad one. The reliable countermeasure is a rule set in advance and kept, such as a stop-loss or a session length (responsible gaming).
• Under the gun: The seat immediately left of the big blind, first to act before the flop. With the whole table still to speak it is the worst seat for information, so correct opening ranges there are the tightest at the table (starting hands, counted).

Tournaments

• Bubble: The point at which the next player eliminated finishes just outside the money. Short stacks slow down to survive into the money, and that is when big stacks should attack: under ICM a marginal call costs a short or middle stack far more than the chip odds suggest.
• Chop: An agreement among remaining players to split the prize pool rather than play it out, usually on chip counts or on an ICM calculation. A chip-count chop favours the big stack over what ICM calls fair, so a short stack offered one can reasonably ask for the ICM figures instead. Some regulated events prohibit chops.
• Freeroll: A tournament with no entry fee, or a situation where you cannot lose but might win. In the second sense it is a hand that cannot lose the pot and might win it all, such as holding the same straight as your opponent with a flush draw as well.
• Guarantee: A minimum prize pool the organiser commits to regardless of entries. If entries fall short the organiser pays the difference, the overlay. An overlay larger than the fees the field paid is one of the few positive-expectation situations in a casino.
• ICM: Independent Chip Model: the conversion from tournament chips into real money value.
• Mystery bounty: A knockout format where each elimination draws a sealed prize. An unopened envelope is worth the bounty pool divided by the envelopes, whatever the headline says.
• Overlay: The shortfall an organiser covers when entries do not reach the guarantee. A $100,000 guarantee that draws $80,000 in entries adds $20,000 nobody paid for, and every entrant's expectation rises by their share of it before any skill is applied.
• Satellite: A tournament whose prize is a seat in a larger one. Price the seat against the fee taken on the way in; it is where most players first meet ICM.

The four worth reading first

House edge is the number every other page on this site is about, and the one casinos never print.

Hold explains why a 1.4% edge produces a 15% loss over a visit, which is the gap most players never account for.

True odds is the comparison that prices any bet in seconds, and shows that a 180:1 payout can be worse value than an even-money one.

Variance is why a night's results tell you nothing about whether a bet was good.

Where an entry quotes a number, that figure comes from the computed sections of this site rather than from another glossary, so the definition and the derivation cannot drift apart. Each entry links to the page where the number is worked out.