Slot and Betting Terms

The articles in this magazine use a recurring set of words. This glossary gathers them in one place with short, plain definitions. Where a term has its own article, the definition links to it.

Slot terms

• Bonus round. A separate feature within a slot, such as free spins or a pick game, usually started by special symbols. See The Impact of Bonus Features in Slot Games.
• Cascade (tumble). A mechanic where winning symbols vanish and new ones fall into their place, possibly forming further wins in the same spin.
• Cluster pays. A grid format in which groups of touching identical symbols win, with no paylines. Explained in Cluster Pays Slots.
• Hit frequency. How often spins produce any win at all, regardless of size.
• Paytable. The game's own list of symbol values, rules and features, found in its information screen.
• Payline. A fixed path across the reels along which matching symbols must land to pay.
• Progressive jackpot. A top prize that grows as players stake money, often across many games. See Progressive Slots.
• RNG (random number generator). The software that decides each spin's outcome independently of previous spins.
• RTP (return to player). The share of all money staked that a game is designed to pay back over a very long run. Always below one hundred percent.
• Scatter. A symbol that counts from any position and usually triggers a feature. See What Are Scatter Symbols in Slots?
• Volatility (variance). How unevenly a game spreads its returns: frequent small wins or rare large ones. See our volatility guide.
• Wild. A symbol that substitutes for regular symbols to complete wins.

Betting terms

• Accumulator (parlay). A single bet combining several selections, all of which must win.
• Double chance. A football bet covering two of the three possible results. See What Is a Double Chance Bet?
• Draw no bet. A bet on one team where a draw returns the stake. See Draw No Bet, Explained.
• Implied probability. The chance of an outcome suggested by its price. Explained in How Odds Work.
• Margin (overround, vig). The built-in share a bookmaker keeps, visible when a market's implied probabilities add up to more than one hundred percent.
• Market. A specific question you can bet on, such as the match result or total goals.
• Void. A bet that is cancelled and refunded rather than won or lost.

Money and safer-play terms

• Bankroll. Money set aside purely for gambling, separate from everyday finances. See bankroll management for sports betting.
• Chasing losses. Increasing stakes or playing longer to win back money already lost, a common warning sign.
• Deposit limit. A cap you set with an operator on how much you can pay in over a period.
• House edge. The operator's long-run advantage in a casino game.
• Self-exclusion. A formal request to be blocked from gambling with one or more operators for a set time.
• Unit. A fixed stake size chosen in advance. See What Is a Unit in Betting?

Missing a word?

If a term on this site is not defined here, tell us through Drop Us a Line and we will add it. All of these definitions are for general understanding by adults aged 18 and over; the official rules of the game or operator always take priority.