Educational glossary · Roulette terms · Risk-aware definitions

Roulette Glossary: Rules, Bets, Odds and Variant Terms Explained

A plain-English glossary of roulette terms, including wheel types, bet names, payouts, house edge, French rules, live dealer terms and betting-system terms. Definitions include risk caveats where a term can be misunderstood.

Glossary edited by Michael Johnson. Fact-checked by Sarah Roberts. Last fact check: May 9, 2026.

Legal, tax and responsible gambling notice

Educational scope: This glossary explains roulette terms. It does not recommend gambling, validate betting systems or predict outcomes.

House edge: Terms such as system, bias or pattern can be misleading. Roulette remains a random game with a house edge.

Tax note: Gambling winnings may be taxable in the United States. Keep records and verify current IRS Topic 419 guidance or consult a qualified tax professional.

Responsible gambling: Stop if terminology, systems or patterns make you feel pressure to gamble. For confidential help, call or text 1-800-MY-RESET or use NCPG support resources.

Quick answer

Roulette terms describe the wheel, table layout, bets, payouts and variants. A term can explain how a bet works, but it does not make that bet profitable or change the odds of the next spin.

How to use this glossary

Use the definitions to understand roulette pages and table rules. For math, use the odds guide. For misconceptions, use the myths guide. For responsible gambling support, use the RG resources page.

Wheel and variant terms

American roulette: A roulette variant with 0, 00 and numbers 1-36. The extra 00 increases the house edge compared with European roulette. Compare European and American roulette.
Auto roulette: A roulette format where a mechanical or automated wheel replaces a human dealer. Rules, pace and limits can differ by operator.
Double zero: The 00 pocket on American roulette. It increases the number of losing outcomes for most bets and raises the house edge.
European roulette: A roulette variant with one zero and numbers 1-36. It has a lower standard house edge than American roulette, but remains negative expected value.
French roulette: A single-zero roulette variant that may include La Partage or En Prison rules. These rules can reduce the house edge on even-money bets when available.
Mini roulette: A smaller roulette variant with fewer numbers and different payout math. Do not assume standard European or American odds.
Racetrack: A betting layout that displays wheel order for announced or neighbor-style bets. It is a layout aid, not a prediction tool.
RNG roulette: Roulette where outcomes are generated by software rather than a streamed physical wheel. RNG roulette has no physical wheel to track for bias.
Single zero: A wheel with one zero pocket. European and many French roulette tables use a single-zero layout.
Wheel layout: The order of numbers around the roulette wheel. It differs from the table betting layout.

Bet type terms

Basket bet: A bet on a small group near zero. In American roulette, the five-number version usually carries a higher house edge than other standard bets.
Column bet: An outside bet covering one vertical column of 12 numbers on the layout. It pays 2:1 on standard tables.
Corner bet: A bet covering four numbers that meet at one corner on the layout. It pays 8:1 on standard tables.
Dozen bet: An outside bet on 1-12, 13-24 or 25-36. It pays 2:1 and still has the table's house edge.
Even-money bet: A 1:1 payout bet such as red/black, odd/even or high/low. These bets hit more often than inside bets, but they are not safe and still have a house edge.
Five-number bet / top-line bet: An American roulette bet covering 0, 00, 1, 2 and 3. It usually has a higher house edge than other standard American roulette bets.
Inside bet: A bet placed on specific numbers or small groups inside the main layout, such as straight up, split, street, corner or six line.
Outside bet: A bet covering larger groups such as red/black, odd/even, high/low, dozens or columns. Larger coverage usually means lower payout.
Red/black: An even-money bet on the color of the winning number. The green zero pocket makes this bet lose on most standard tables.
Roulette chips: Table-specific chips used to identify each player's bets. Chip color identifies the player, not the payout value across all tables.
Six line: A bet covering two adjacent rows of three numbers. It pays 5:1 on standard roulette tables.
Split bet: A bet covering two adjacent numbers. It pays less than a straight-up bet because it covers more numbers.
Straight up: A bet on one number. It has the highest standard payout and lowest hit probability among common roulette bets.
Street bet: A bet on a row of three numbers. It pays 11:1 on standard roulette tables.
Table layout: The betting grid where chips are placed. It is different from the physical order of numbers around the wheel.

Odds and payout terms

Expected value: The long-run mathematical average outcome of a bet. Standard roulette bets have negative expected value for the player.
Hit probability: The chance that a bet wins on one spin. Higher hit probability usually means lower payout.
House edge: The casino's long-run mathematical advantage. It is not a prediction for one session, but it explains why roulette has negative expected value.
Payout: The amount paid on a winning bet. Roulette payouts are lower than true odds because of the zero pocket.
Return to player / RTP: The theoretical long-run return percentage before individual session variance. RTP is not a guarantee for any one player.
True odds: The mathematically fair odds of an outcome. Roulette payouts are lower than true odds, which creates the house edge.
Variance: The natural swing between short-term results and long-run expectation. Variance can make random results look meaningful.
Volatility: The size and frequency of swings in results. Low-hit, high-payout bets usually feel more volatile.

French roulette and call-bet terms

Announced bets: Traditional call bets placed on wheel sectors or number groups. Online availability and exact rules vary by table.
En Prison: A French roulette rule that can hold an even-money bet after zero. How it resolves depends on the table's exact rule set.
La Partage: A French roulette rule where half of an even-money bet is returned when the ball lands on zero. It applies only when the table offers that rule.
Neighbors: A call-bet term for numbers adjacent to a chosen number on the wheel. It describes coverage, not a prediction.
Tiers du cylindre: A traditional call bet covering a sector of the wheel. It can be useful for understanding table language, not for overcoming the house edge.
Voisins du zero: A traditional call bet covering numbers near zero on the wheel. It is a coverage term, not evidence of a better expected value.

Live dealer, RNG and mobile terms

Bet confirmation: The point at which a digital table accepts a bet. Connection issues or timing can affect whether a bet is accepted.
Croupier: The person who operates a roulette table in a land-based or live dealer setting.
Game provider: The company supplying the roulette game or live dealer studio. Provider, rules and operator terms should be checked separately.
Geolocation: Technology used to verify where a player is located. Real-money access can be blocked if location checks fail or if play is not permitted.
Live dealer roulette: A streamed roulette game using a physical wheel and human dealer. It still has table rules, limits, provider controls and a house edge.
Maximum bet: The largest stake a table allows on a bet or bet type. Maximums can limit staking systems and vary by table.
Minimum bet: The smallest stake a table allows. Minimums affect session cost and should be checked before play.
Stream delay: Lag between the live table and the player's device. It can affect user experience and bet timing, but should not be treated as an advantage.
Table limits: The minimum and maximum bets allowed by a table. Limits affect exposure and can also constrain staking systems.
Wagering requirement: A promotion rule requiring a player to wager a certain amount before withdrawing bonus-related funds. Roulette contribution can differ from other games.

Betting-system terms

Betting systems are stake-size patterns. They do not change the roulette wheel, the payout table, the probability of the next spin or the house edge.

Bankroll: The money set aside for gambling entertainment. It should not include funds needed for bills, debt, savings or essentials.
Chasing losses: Increasing play to recover money already lost. This is a responsible gambling warning sign.
D'Alembert system: A linear staking pattern that increases by one unit after a loss and decreases by one unit after a win. It does not change expected value.
Fibonacci system: A sequence-based staking pattern. Slower growth than Martingale does not make it safe or profitable.
Labouchere system: A cancellation staking pattern built around a sequence. Target-based framing can be psychologically risky because losses can expand the sequence.
Martingale: A negative progression where the stake doubles after losses. It can escalate quickly and should not be treated as a recovery method.
Positive progression: A staking pattern that increases after wins. It changes exposure, not the probability of the next spin.
Stop-loss: A pre-set loss limit for ending a session. It can help define a budget boundary but does not change game odds.

Advantage-play terms

The following terms are included for historical context. They are not instructions and should not be treated as practical methods for ordinary online players.

Biased wheel: A historical term for a physical roulette wheel suspected of producing non-random results because of rare mechanical defects. This generally does not apply to RNG roulette, and device-assisted tracking can create legal or account risks.
Dealer signature: A historical theory involving alleged repeatable dealer behavior. Modern live dealer roulette is monitored and governed by operator terms; it should not be treated as a reliable strategy.
Device-assisted play: Use of software, apps or hardware to analyze or project casino outcomes. Laws and operator terms vary, and this can create legal or account consequences.
Kesselgucken: A historical wheel-watching term. It should not be treated as an online strategy or as a reason to use tracking tools.
Sector betting: Betting on a section of the wheel. Sector coverage changes which numbers are covered, not the randomness of the next spin.
Visual ballistics: A historical advantage-play concept involving observation of wheel and ball movement. It is not a casual online strategy and should not be used as a basis for real-money play.
Wheel clocking: A historical term for tracking wheel outcomes or sectors. Device or software-assisted tracking can violate laws or operator terms.

Quick payout reference

Common European roulette bet types and caveats
Bet type	Payout	European probability	Caveat
Straight up	35:1	1/37	Highest payout, lowest hit probability.
Split	17:1	2/37	Covers two adjacent numbers.
Street	11:1	3/37	Covers one row of three numbers.
Corner	8:1	4/37	Covers four adjacent numbers.
Six line	5:1	6/37	Covers two rows of three numbers.
Dozen / column	2:1	12/37	Middle coverage, still negative EV.
Even-money	1:1	18/37	Higher hit probability, still negative EV.