Slot and casino glossary
52 slot and casino terms in plain English, from RTP and volatility to wagering requirements, licences and the language of slot streams. For how we calculate the numbers on SpinScout, see our methodology.
Last updated 2026-11-10
B
- Bankroll
- The total amount of money you have set aside for gambling, kept separate from money you need for anything else. Sizing bets as a small share of your bankroll lets it last through the losing streaks every slot has.
- Base game
- The ordinary spins of a slot, outside any bonus round or free spins. On high-volatility games, most of the return is paid in the bonus, so the base game pays little on its own.
- Bonus buyalso: Feature buy
- An option to pay a fixed price, usually a multiple of your stake such as 100x, to trigger a slot's bonus round immediately instead of waiting for it in the base game. The RTP of the buy can differ slightly from the base game. Bonus buys are banned in some markets, including Great Britain. Browse slots
- Bonus hunt
- A streaming format where the streamer spins many different slots until each one triggers its bonus round, saving the bonuses without opening them. The total amount spent becomes the hunt's "start", which the bonuses later have to beat. Live Kick streamers
- Bonus opening
- The second half of a bonus hunt, when the streamer plays the saved bonus rounds one by one and tallies the wins against the start amount. Viewers often track the running average win multiple needed to break even. Live Kick streamers
- Bonus round
- A special feature inside a slot, such as free spins, a pick-and-win game or a hold-and-win round, triggered by landing certain symbols. Bonus rounds usually carry the slot's biggest wins.
C
- Cascading reelsalso: Tumble, avalanche
- A mechanic where winning symbols disappear after a win and new symbols drop into their place, which can create further wins from the same spin. Many cascading slots add a multiplier that grows with each cascade.
- Cashback
- A promotion that returns a percentage of your net losses over a period, for example 10% weekly. Cashback paid as real money is worth more than cashback paid as bonus funds with a wagering requirement. Casinos with cashback
- Cluster pays
- A pay system where you win by landing a group of matching symbols touching each other horizontally or vertically, usually five or more, instead of along paylines. Cluster slots are often played on larger grids such as 7x7 and usually combine with cascading reels.
- Crypto casino
- An online casino that accepts deposits and pays withdrawals in cryptocurrencies such as Bitcoin, Ethereum or USDT. Many are licensed in Curaçao or similar jurisdictions rather than by national regulators, so check the licence before depositing. Casinos that accept Bitcoin
- Curaçao licence
- A licence issued in Curaçao, historically the most common licence among international and crypto casinos. Since a 2023–2024 reform, licences are issued directly by the Curaçao Gaming Authority instead of through master-licence holders. Player protection standards are generally lighter than under the UKGC or MGA. Curaçao-licensed casinos
D
- Demo mode
- A free-play version of a slot that uses play money, offered by most providers. It plays the same game, so it's a good way to learn the features and get a feel for the volatility. Winnings in demo mode can't be withdrawn.
- Deposit limit
- A cap you set on how much you can deposit per day, week or month. Licensed casinos must offer deposit limits, and lowering a limit usually takes effect immediately, while raising one comes with a waiting period.
F
- Free spins (feature)
- A slot bonus round where the reels spin for a set number of rounds without deducting your stake, often with extra features such as multipliers or sticky wilds. They are usually triggered by landing three or more scatter symbols.
- Free spins (promotion)
- A casino offer that gives you a number of spins on a specific slot at a fixed stake, as part of a welcome or reload bonus. Winnings from them are often paid as bonus money with a wagering requirement and a cap on how much you can cash out. Casinos with free spins
G
- Game weightingalso: Wagering contribution
- The share of each bet that counts towards a wagering requirement. Slots usually count 100%, while table games and live casino often count 10–20% or nothing at all. A low weighting multiplies how much you need to bet to clear a bonus. Wagering calculator
H
- Hit frequency
- How often a spin returns any win, expressed as a percentage or as "1 in X" spins. A 25% hit frequency means roughly one winning spin in four. Many of those hits pay less than the stake, so a high hit frequency doesn't mean the slot is profitable.
- Hold and winalso: Hold and spin
- A bonus round where special symbols, often coins with cash values, lock in place and the remaining positions respin, usually three times. Each new special symbol resets the respin count, and filling the whole grid often pays a jackpot.
- House edge
- The casino's average profit on every bet, the opposite of RTP. A slot with 96% RTP has a 4% house edge: over a very large number of spins, the casino keeps about 4% of everything wagered.
J
- Jackpot
- A large prize on top of the normal paytable. A fixed jackpot pays a set amount, while a progressive jackpot grows with a small share of every bet until someone wins it, sometimes across a network of casinos.
K
- KYCalso: Know your customer
- The identity checks a licensed casino must run, typically asking for a photo ID, proof of address and sometimes proof of where your money comes from. Casinos often request it at your first withdrawal, so verifying early avoids delays.
L
- Licence
- Official permission from a gambling regulator to run a casino in a jurisdiction. A licence binds the operator to rules on fair games, player funds, complaints and responsible gambling. Licensed casinos must display their licence, usually in the site footer. How we record licences
- Live dealeralso: Live casino
- Table games such as blackjack, roulette and baccarat, plus game shows, streamed in real time from a studio with a human dealer. You place bets through an on-screen interface while the physical cards or wheel decide the result.
M
- Max bet with bonus
- The largest stake you're allowed per spin or hand while playing with an active bonus, often a fixed amount like 5 in your currency. Breaking it, even once, can let the casino void the bonus and any winnings from it.
- Max win
- The largest win a slot can pay on a single spin or bonus round, stated as a multiple of the stake, such as 5,000x. Once it's reached, the round usually ends immediately.
- Megaways
- A reel mechanic licensed by the studio Big Time Gaming in which each reel shows a random number of symbols on every spin, so the number of ways to win changes from spin to spin, up to 117,649. Wins pay for matching symbols on adjacent reels from left to right.
- MGAalso: Malta Gaming Authority
- The gambling regulator of Malta and one of the most widely held licences among European online casinos. An MGA licence comes with requirements on player fund protection, dispute resolution and responsible gambling tools. MGA-licensed casinos
- Multiplier
- A value that multiplies a win, such as 2x or 100x. Multipliers can sit on symbols, apply to a whole spin, or grow during free spins, and they drive most of the top wins on modern high-volatility slots.
N
- No-deposit bonus
- A small bonus, in cash or free spins, given for signing up without having to deposit. They usually carry high wagering requirements and a low cap on how much you can withdraw, so treat them as a free trial rather than real value. No-deposit bonuses
P
- Paylines
- Fixed lines across the reels along which matching symbols must land to pay, such as 10 or 20 lines on a classic 5x3 slot. Some slots let you choose how many lines to play, while "ways" slots (243 ways, Megaways) pay matching symbols on adjacent reels without fixed lines.
- Provably fair
- A verification method used mainly by crypto casinos for their own games. Before a bet, the casino commits to a hidden server seed by publishing its hash. The result is calculated from that seed, your client seed and a counter, so afterwards you can check the casino didn't change the outcome.
- Provideralso: Game studio
- The company that develops a slot and supplies it to casinos, for example Pragmatic Play, Hacksaw Gaming or NetEnt. The provider sets the game's RTP options, volatility and max win; the casino only chooses which RTP version to run. Slot providers
R
- Ref codealso: Referral code, affiliate code
- A code or link, often promoted by streamers, that tags your sign-up as referred by them. The referrer usually earns a commission from the casino, and some codes add an extra bonus or rakeback for you. How affiliate links work
- Regulator
- The public body that licenses and supervises gambling in a jurisdiction, such as the UK Gambling Commission, the Malta Gaming Authority or Sweden's Spelinspektionen. Regulators publish registers of licensees, which is the most reliable way to check a licence.
- Retrigger
- Winning extra free spins during a free spins round, usually by landing scatter symbols again. Retriggers extend the bonus and often keep any multipliers built up so far.
- RNGalso: Random number generator
- The software that decides the result of every spin. Each spin is independent, so a slot is never "due" a win after a dry spell. In regulated markets, RNGs are tested by independent labs before games go live.
- RTPalso: Return to player
- The share of all money wagered on a slot that it pays back over a very large number of spins, set by the provider. A 96% RTP means about 96 returned per 100 wagered in the long run; in a single session your result can be far above or below that. Slot RTP by provider
- RTP rangealso: Variable RTP
- Many slots are released in several RTP versions, for example 96%, 94% and 92%, and each casino chooses which one to run. The same game can return noticeably less at one casino than another; the game's info or rules screen shows the version you're playing. Where our RTPs come from
S
- Scatter
- A symbol that pays or triggers a feature wherever it lands on the reels, without needing to sit on a payline. Landing three or more scatters usually starts the free spins round.
- Self-exclusion
- A tool that blocks you from gambling at a casino for a chosen period, from months to years, and can't be reversed early. National schemes such as GAMSTOP in Great Britain apply it across every licensed operator at once. A shorter break is usually called a cooling-off period or time-out.
- Session
- One continuous period of play, from when you start to when you stop. Setting a time and loss limit for each session before you begin is one of the simplest ways to keep gambling under control.
- Slot streamer
- A content creator who broadcasts slot play live, mostly on Kick, often running bonus hunts and promoting a casino with a ref code. Streamers are frequently paid by the casinos they play at, so their balances and results aren't a guide to what you can expect. Kick streamers we track
- Sticky bonus
- A bonus that can be played with but never withdrawn: when you cash out, the bonus amount is removed and only winnings above it are paid. The opposite is a non-sticky bonus, where you play your real money first and can withdraw before the bonus is used.
- Sticky wild
- A wild symbol that stays in place for several spins, typically through the rest of a free spins round, helping form wins on every spin it remains.
U
- UKGCalso: UK Gambling Commission
- The regulator for gambling in Great Britain and one of the strictest in the world. Its rules include a ban on credit card deposits, a ban on bonus buys, stake limits per spin on online slots and mandatory affordability and identity checks. UKGC-licensed casinos
V
- Volatilityalso: Variance
- How a slot's returns are spread out. Low-volatility slots pay small wins often, while high-volatility slots go through long dry spells between rare large wins. Two slots with the same RTP can feel completely different because of volatility.
W
- Wagering requirementalso: Playthrough, rollover
- The amount you must bet before bonus money or bonus winnings can be withdrawn, stated as a multiple such as 35x the bonus (or of the deposit plus bonus). A 100 bonus at 35x means 3,500 in bets, and the house edge on all that play is the real cost of the bonus. Wagering calculator
- Welcome bonus
- An offer for new players on their first deposit or deposits, most often a percentage match such as 100% up to a set amount, sometimes with free spins. Check the wagering requirement, max bet, game weighting and expiry before accepting one. Welcome bonuses
- Wild
- A symbol that substitutes for other symbols to complete wins, usually all except scatters and bonus symbols. Variants include expanding wilds that fill a whole reel, sticky wilds and wilds that carry multipliers.
- Win multiplealso: "x" win
- A win expressed relative to the stake: a 1,000x win on a 1 bet pays 1,000. Streamers quote wins this way so results are comparable regardless of bet size.
- Withdrawal limit
- The maximum a casino will pay out per transaction, day, week or month. A low limit can mean a large win is paid in instalments over months, so check the limits in the terms before you play.
- Withdrawal timealso: Pending period
- How long a payout takes, made up of the casino's own processing or pending period plus the time the payment method needs. E-wallets and crypto are usually fastest; card and bank transfers can take several working days.
Gambling should be entertainment, not a way to make money. If it stops feeling that way, see BeGambleAware or Gambling Therapy. 18+ only.