58 defined terms

Casino math glossary.

Plain-language definitions connected to the deeper lessons and calculations that use them.

58 terms

Risk and evidence

Bankroll

Money deliberately set aside for play; it is an exposure limit, not an advantage.

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Game rules

Base game

The required wager and settlement structure before optional side bets or progressives are added.

Core math

Break-even probability

The win probability required for an offered payout to have zero expected value.

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Game rules

Buy bet

A craps number wager paid at true odds subject to a commission.

Core math

Card removal

Updating probabilities because known cards are no longer available among unseen combinations.

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Action and pricing

Coin-in

Total money wagered through an electronic game, not the cash originally inserted.

Action and pricing

Commission

A fee charged on a wager, win, or transaction; its basis and timing affect effective value.

Core math

Conditional expected value

Expected value recalculated for the information known at a specific decision point.

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Core math

Conditional probability

The probability of an event after restricting the sample space to states compatible with known information.

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Risk and evidence

Confidence interval

A range generated by a stated statistical procedure to communicate sampling uncertainty.

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Game rules

Configuration

The exact approved rules, pay table, denomination, features, and settings used by a game.

Risk and evidence

Correlation

The extent to which two results tend to move together rather than independently.

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Risk and evidence

Covariance

A signed measure of how two outcomes vary together; it affects combined variance.

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Action and pricing

Decision rate

The number of resolved wagers or meaningful game decisions per unit of time.

Core math

Denominator

The amount used as the base of a percentage, such as initial wager or average total action.

Game rules

Dealer qualification

A minimum dealer hand required for specified comparisons or wagers to settle normally.

Core math

Element of risk

Expected casino win divided by average total money wagered, often used when later wagers vary.

Risk and evidence

Enumeration

Counting every compatible outcome exactly rather than estimating by random simulation.

Core math

Expected loss

Total action multiplied by the applicable house edge under the same model and denominator.

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Core math

Expected value (EV)

The probability-weighted average net result of all mutually exclusive outcomes.

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Core math

Fair odds

The payout that makes a wager break even before commissions or other costs.

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Action and pricing

Feature contribution

The portion of a game’s theoretical return produced by a specified bonus or feature.

Action and pricing

For-one payout

A return convention that may include the original stake; five-for-one commonly means four units of net profit.

Risk and evidence

Gambler’s fallacy

The false belief that independent outcomes must quickly balance after a streak.

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Risk and evidence

Hit frequency

The share of trials producing an award under a stated definition, including awards smaller than the wager when rules count them.

Action and pricing

Hold

An observed accounting ratio based on money retained relative to buy-ins or handle; it is not synonymous with house edge.

Core math

House edge

The casino’s expected win expressed as a percentage of a clearly stated wager denominator.

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Core math

Implied probability

The break-even probability encoded by an offered payout before adjustments for pushes or multiple prizes.

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Core math

Independent events

Events for which observing one does not change the probability distribution of the other.

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Action and pricing

Initial wager

The amount committed before later decisions add, remove, or multiply exposure.

Action and pricing

Jackpot baseline

The reset or reference value already included in a base return before meter growth is added.

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Game rules

Maximum aggregate payout

A cap on the total amount payable from one hand, round, or linked set of wagers.

Risk and evidence

Monte Carlo simulation

Randomly sampling a defined model many times to estimate an outcome distribution.

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Core math

Mutually exclusive outcomes

Outcome categories constructed so no single trial can belong to more than one category.

Game rules

Natural

A qualifying initial-card result with special settlement, such as a two-card blackjack.

Action and pricing

Net payout

Profit excluding return of the original stake; a 3:1 net payout wins three units plus the stake back.

Core math

Optimal strategy

The legal decision policy with the highest expected value under the exact stated rules.

Risk and evidence

Outcome distribution

Every possible net result paired with its probability.

Game rules

Pay table

The complete schedule mapping qualifying outcomes to awards, including footnotes and caps.

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Game rules

Place bet

A removable craps wager that a selected number appears before seven, paid at posted odds.

Action and pricing

Progressive

A prize meter that changes as eligible wagers are made or jackpots are awarded.

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Game rules

Push

A settlement returning the applicable stake with neither net win nor loss.

Game rules

Qualification

A condition that must be met before a hand, feature, payout, or wager is eligible.

Risk and evidence

Random number generator (RNG)

The system producing values mapped to outcomes in an electronic game’s approved implementation.

Core math

Return to player (RTP)

Expected prizes divided by total qualifying wagers under a specific model and configuration.

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Risk and evidence

Risk of ruin

The probability of reaching a defined bankroll boundary under a stated game, staking rule, and horizon.

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Risk and evidence

Sample size

The number of observations or simulated trials used to estimate a quantity.

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Game rules

Side bet

An optional wager with its own event definition and pay table, even when it uses the base game’s cards.

Risk and evidence

Standard deviation

The square root of variance, expressing result spread in the original units.

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Risk and evidence

Stopping rule

A predeclared condition ending future action; it controls exposure but does not improve prior wagers.

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Core math

Theoretical loss

Another name for expected loss under a specified amount of action and house edge.

Action and pricing

To-one payout

A net-profit convention: five-to-one normally means five profit units plus return of stake.

Core math

True odds

The fair net payout implied by the underlying win and loss probabilities.

Risk and evidence

Variance

The probability-weighted squared spread of outcomes around expected value.

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Action and pricing

Vigorish (vig)

A commission or pricing charge; in craps its collection basis and timing can materially change the effective edge.

Risk and evidence

Volatility

A practical description of how concentrated or dispersed a game’s result distribution is.

Action and pricing

Wagering requirement

Qualifying action required before a bonus or related winnings become withdrawable.

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