Casino sites, bonus terms and slot rules are full of jargon. Words like RTP, volatility, wagering and sticky bonus decide how a game plays and what a bonus is really worth, yet they are rarely explained on the page where you need them. This A–Z glossary defines the most common casino and slot terms in plain English.
A–B
Autoplay – a setting that spins a slot automatically for a chosen number of rounds. Some countries restrict or ban it. If you use it, set a loss limit so it stops on its own.
Bankroll – the total amount of money you have set aside for gambling. It should be money you can afford to lose, kept separate from bills and savings.
Bonus buy – a slot feature that lets you pay a fixed price, often a multiple of your stake, to enter the bonus round directly. It raises the cost of each round and is banned in some countries and often excluded from bonus play.
Bonus code – a word or code you enter at registration or in the cashier to activate a specific promotion. Without it, the offer may not be added.
Bonus round – a special feature inside a slot, such as free spins or a pick-and-win game, usually triggered by scatter symbols.
C–D
Cascading reels – a slot mechanic where winning symbols disappear and new ones drop into their place, allowing several wins from one spin. Also called tumbling or avalanche reels.
Cashback – a refund of part of your net losses over a set period, often paid as cash or low-wagering bonus money. Read our guide to cashback casinos.
Cluster pays – a slot system where you win by landing groups of matching symbols that touch each other, instead of lining them up on paylines.
Comp points – loyalty points earned as you bet, which can be exchanged for bonuses or rewards.
Demo mode – playing a game with virtual credits instead of real money. Useful for learning how a slot works before risking anything.
Deposit limit – a cap you set on how much you can deposit per day, week or month. Licensed casinos must offer this tool.
Deposit match – a bonus that adds a percentage of your deposit as bonus money, for example 100% up to €200. See our welcome bonus guide.
E–G
E-wallet – an online payment account, such as PayPal or Skrill, that sits between your bank and the casino. Often one of the fastest withdrawal options.
Expiry – the time limit for using a bonus or completing its wagering. When it passes, the bonus and related winnings are removed.
Free spins – spins on a slot that cost you nothing, either as a casino promotion or as a feature inside the game. Promotional free spins usually have a fixed stake and wagering on winnings.
Game weighting – how much each game counts towards wagering. Slots often count 100%, while table and live games may count 0%–20%.
H–K
High roller – a player who bets large amounts. Some casinos have separate high-roller bonuses and limits.
Hit frequency – how often a slot produces a win of any size, shown as a percentage or ratio. A high hit frequency does not mean a high return, because many wins can be smaller than the stake.
House edge – the built-in mathematical advantage a game gives the casino, equal to 100% minus the RTP. A 96% RTP slot has a 4% house edge.
Jackpot – the largest prize a game can pay. A fixed jackpot is a set amount; a progressive jackpot grows with every bet until someone wins it.
KYC (know your customer) – the identity, age and address checks a licensed casino must carry out, usually before your first withdrawal.
L–M
Licence – official permission from a gambling regulator to operate. A valid licence means the casino must follow rules on fairness, payments and player protection.
Live casino – table games streamed in real time with a human dealer, such as roulette, blackjack and game shows.
Max bet – the largest stake allowed per spin or hand while a bonus is active. Breaking it can void the bonus.
Max cashout – the most you can withdraw from bonus winnings. Anything above the cap is removed. Both terms are covered in our guide to bonus terms.
Multiplier – a feature that multiplies a win by a set amount, for example 2x or 10x.
N–P
No deposit bonus – free spins or bonus money credited without a deposit, usually with strict terms. Read our full no deposit bonus guide.
Non-sticky bonus – a bonus kept separate from your real money. You play with your own cash first and can usually withdraw real-money winnings before the bonus is used. Also called a parachute bonus.
Paylines – the lines across the reels on which matching symbols must land to win. Slots can have from one to dozens of fixed or adjustable paylines.
Pending period – the time a withdrawal waits for approval before it is processed, typically from zero to a few days.
Playthrough – another word for wagering requirement.
R
Reality check – a pop-up reminder that shows how long you have been playing and how much you have won or lost.
Reels – the vertical columns of symbols on a slot. Most video slots have five reels.
Reload bonus – a deposit bonus for existing players, usually smaller than a welcome bonus.
RNG (random number generator) – the software that decides the result of each spin or hand at random. Licensed games have their RNG tested by independent labs.
RTP (return to player) – the share of all money bet that a game is designed to pay back over a very large number of rounds, for example 96%. It says nothing about a single session. Learn more in slot RTP explained.
S–T
Scatter – a slot symbol that pays or triggers a feature wherever it lands, without needing to be on a payline.
Self-exclusion – a tool that blocks you from gambling for a chosen period, at one casino or, in some countries, at all licensed sites.
Stake – the amount you bet on a single spin, hand or round.
Sticky bonus – a bonus that can be played with but never withdrawn itself. It is removed when you cash out, leaving only the winnings.
Table games – casino games played on a table layout, such as blackjack, roulette and baccarat, either digital or live.
V–W
VIP programme – a loyalty scheme that rewards regular players with perks such as cashback, faster withdrawals or a personal manager. It should never be a reason to bet more.
Volatility – how a slot's wins are spread out. Low volatility means frequent small wins; high volatility means fewer but larger wins and longer losing runs. Also called variance.
Wagering requirement – how many times you must bet a bonus (or bonus plus deposit) before you can withdraw winnings from it. Our beginner's guide to wagering explains it step by step.
Ways to win – a slot system that pays matching symbols on adjacent reels from left to right, whatever their row, instead of using fixed paylines.
Welcome bonus – the offer for a new player's first deposit or deposits, often a match bonus with free spins.
Wild – a symbol that substitutes for other symbols to complete winning combinations. Variants include expanding, sticky and walking wilds.
Play responsibly
Knowing the terms helps you make informed choices, but no knowledge changes the house edge. Online gambling is for adults only (18+, or the legal age in your country). Set a budget and time limits before you play, and visit our responsible gambling page for tools and support.
