Slot glossary
Slot reviews are full of jargon. Here are 25 terms you will meet on this site and elsewhere, each explained in a sentence.
By Ryan Jessop. Last checked .
Key takeaways
- 25 terms, A to Z.
- Notes on what is not available in Britain.
- Links to fuller guides where a term needs one.
Slot terms A to Z
- Autoplay
- Automatic repeated spins. Not permitted on online slots in Britain.
- Base game
- Ordinary spins, outside any feature.
- Bonus buy
- Paying to trigger a feature directly. Not offered to UK players.
- Cascade
- See Tumble.
- Demo
- A free-play version using pretend credits. See free slots.
- Expanding symbol
- A symbol that grows to cover a reel, as in Book of Dead.
- Free spins
- Spins that cost nothing, triggered in play or given by a casino.
- Hit frequency
- How often a spin returns anything at all.
- House edge
- The casino's long-run share of stakes: 100% minus RTP.
- Max win
- The largest possible win on one spin, as a multiple of the stake.
- Megaways
- A licensed mechanic in which the number of symbols per reel changes each spin.
- Multiplier
- A value that multiplies a win.
- Payline
- A set path across the reels on which matching symbols pay.
- Pays anywhere
- Wins formed by enough matching symbols anywhere on the grid.
- Paytable
- The in-game screen listing symbol values and rules.
- Progressive jackpot
- A prize that grows with every stake until won.
- RNG
- Random number generator: the software that decides each spin.
- RTP
- Return to player. See RTP explained.
- Scatter
- A symbol that pays or triggers features from any position.
- Stake
- The amount bet on one spin. Capped at £5 in Britain, or £2 for ages 18 to 24.
- Tumble
- Winning symbols are removed and replaced, allowing further wins.
- Variance
- Another word for volatility.
- Volatility
- How a slot spreads its payouts. See volatility explained.
- Wagering requirement
- The stakes needed before bonus money becomes cash; capped at 10x in Britain.
- Wild
- A symbol that substitutes for others.
The five terms that matter most
If you learn only five, make them RTP, volatility, max win, stake and paytable. Between them they tell you the price of a slot, how it behaves, its ceiling, what you are risking per spin and where to check all of it. Our slot reviews lead with exactly those figures.
Go deeper
Features are covered at length in slot features explained, the mechanics in how slots work and the regulations in the UK slot rules.
Play safely
Slots are fast, and they are designed so the house wins over time. Decide what the session is worth to you before you open a game, set a deposit limit, and stop when the money is gone. Free, confidential help is available from the National Gambling Helpline on 0808 8020 133. Our safer gambling page lists the tools and services.
Frequently asked questions
What does RTP mean?
Return to player: the long-run percentage of stakes a slot pays back.
What is variance?
Another word for volatility.
What is a payline?
A path across the reels on which matching symbols pay.
What does max win mean?
The largest win one spin can produce, as a multiple of the stake.