Roulette Glossary: Every Term on the Felt Explained
Roulette has three vocabularies layered on top of each other: the physical language of the wheel, the betting language of the felt, and — in the on-chain era — the cryptographic language of provable fairness. This glossary covers all three, so the next time you see voisins du zero or commit-reveal on a screen, you know exactly what is being said and what it costs.
Put the vocabulary to work →The wheel and the table
Pocket: one of the numbered compartments on the wheel where the ball settles; a single-zero wheel has 37, an American wheel 38. Zero: the green house pocket, numbered 0, that makes even-money bets lose more often than they win; its presence creates the 2.70% single-zero house edge. Double zero: the second green pocket (00) on American wheels, raising the edge to 5.26%. Croupier: the casino employee who spins the wheel, calls the result and settles bets — from the French for one who rides behind; online, software plays this role. Layout: the printed betting grid on the table felt. House edge: the percentage of every wager the casino keeps on average over the long run; on a single-zero wheel it is 2.70% on almost every bet. RTP (return to player): the mirror of the edge — a 2.70% edge means a 97.30% RTP.
Inside bets
Straight up: a bet on one number, paying 35:1 with a 1/37 chance on a single-zero wheel. Split: one chip covering two adjacent numbers on the grid, paying 17:1. Street: three numbers in a row (such as 7-8-9), paying 11:1. Corner: four numbers meeting at an intersection, paying 8:1; also called a square. Six line: two adjacent streets — six numbers — paying 5:1; also called a double street. Every one of these carries the same 2.70% single-zero edge, because the payouts scale exactly with the numbers covered. Inside bets are the high-variance end of the felt: rarer wins, bigger multiples.
Outside bets
Red/black: an even-money bet on the winning color; 18 of 37 numbers qualify, so it wins 48.6% of the time on single zero. Odd/even: an even-money bet on the parity of the winning number; zero counts for neither side. High/low: an even-money bet on 19-36 (high) or 1-18 (low). Dozens: a 2:1 bet on one of the three blocks of twelve — 1-12, 13-24 or 25-36. Columns: a 2:1 bet on one of the three vertical columns of the layout, twelve numbers each. Outside bets are the low-variance end of the table: frequent small wins, same underlying edge as the inside bets, and the only wagers affected by the la partage and en prison rules below.
Announced and call bets (the French set)
These are wheel-based bets, placed by announcement, that cover sections of the wheel rather than shapes on the felt. Voisins du zero (neighbors of zero): a nine-chip bet covering the 17 numbers nearest zero on the wheel, from 22 around to 25, using a mix of splits, corners and a trio. Tiers du cylindre (thirds of the wheel): six chips on splits covering the 12 numbers roughly opposite zero, from 27 to 33. Orphelins (orphans): the eight numbers belonging to neither section, covered with one straight up and four splits. A neighbors bet backs one number plus the two pockets on each side of it on the wheel. Call bets are tradition and geometry, not value — each component chip still pays standard inside-bet odds at the standard edge.
Rules that cut the edge
La partage (the sharing): on some single-zero tables, when the ball lands on zero, even-money bets lose only half their stake instead of all of it. This halves the house edge on those bets to about 1.35%, making la partage even-money bets among the cheapest wagers in any casino. En prison (in prison): a variant where, instead of surrendering half, your even-money stake is locked on the table for the next spin; win that spin and the stake is returned in full. Both rules apply only to even-money outside bets — red/black, odd/even, high/low — never to dozens, columns or inside bets. When comparing tables, these two words matter more than any bonus banner.
Online and provably-fair terms
RNG (random number generator): the algorithm that produces outcomes in digital roulette, replacing the physical wheel and ball. Server seed: a secret random value generated by the casino that drives the outcome; the core of provably-fair systems. Client seed: a value contributed from your side and mixed with the server seed, ensuring the house alone does not control the input. Commit-reveal: the two-step scheme that makes fairness checkable — the house publishes a cryptographic hash of the server seed (the commitment) before any bet, then reveals the seed itself afterward so you can verify the hash matches and recompute the result. On Llamabet the commitment is published on the Sui blockchain before you bet, the seed is revealed after the round, and payouts land in your wallet on-chain in about a second. Related onboarding vocabulary: zkLogin lets you derive a Sui wallet by signing in with Google — no seed phrase — while players with an existing Sui wallet such as Slush can connect directly. Minimum bet on the Llamabet wheel: 1 SUI.
Frequently asked questions
What is the difference between en prison and la partage in roulette?
Both soften the zero for even-money bets on single-zero tables. La partage returns half your stake immediately when zero hits. En prison locks the full stake for one more spin — win it and the stake comes back whole. Either rule cuts the house edge on even-money bets from 2.70% to about 1.35%.
What do voisins, tiers and orphelins mean in roulette?
They are French announced bets covering physical sections of the wheel: voisins du zero is 17 numbers around zero placed with nine chips, tiers du cylindre is the 12 numbers opposite zero placed with six chips, and orphelins is the eight leftover numbers. They carry the same per-chip edge as ordinary inside bets.
What does commit-reveal mean in provably-fair roulette?
It is the scheme that lets you verify a spin. The casino commits by publishing a hash of its secret server seed before you bet — on Llamabet, on the Sui blockchain — then reveals the seed after the round. You can check the hash matches and recompute the winning number, proving the outcome was fixed before your wager.