Key takeaways
- 21 terms, A to Z.
- Notes on what Britain does not allow.
- Links to fuller pages.
A to Z
- Base game
- Ordinary spins outside any feature.
- Bonus buy
- Paying to trigger a feature. Not offered in Britain.
- Cascade
- Another word for a tumble.
- Cash collect
- A collector symbol gathers values shown on other symbols.
- Expanding symbol
- A symbol that grows to cover reels in a feature.
- Expanding wild
- A wild that fills its reel.
- Free spins
- Spins that cost nothing, from a feature or a casino offer.
- House edge
- 100% minus RTP.
- Max win
- The largest win on one spin, as a multiple of stake.
- Megaways
- A mechanic with a changing number of ways to win.
- Multiplier
- A value that multiplies a win.
- Payline
- A path on which matching symbols pay.
- Paytable
- The slot's list of payouts and rules.
- Pick bonus
- A round where you choose hidden prizes.
- Progressive jackpot
- A prize pool that grows with every stake.
- RNG
- Random number generator.
- RTP
- Return to player.
- Scatter
- A symbol that triggers from any position.
- Tumble
- Winners removed and replaced.
- Volatility
- How a slot spreads its payouts.
- Wild
- A substitute symbol.
Nine more terms
- Both ways
- Paylines counted from either edge.
- Demo mode
- Free play with pretend credits.
- Hit frequency
- The share of spins that return anything.
- Hold and win
- A collect feature with re-spins.
- Line bet
- The stake on one payline.
- Pays anywhere
- Wins from enough matching symbols anywhere.
- Retrigger
- Winning more free spins during free spins.
- Sticky wild
- A wild that stays for several spins.
- Total bet
- The full cost of one spin.
Words that mean the same
| You may see | It means |
|---|---|
| Online slots, slot games, slot machines, video slots | The same thing |
| Cascade, avalanche, tumble | Winners removed and replaced |
| Variance | Volatility |
| Bonus round, feature | A special part of the game |
| Fruit machine | A classic slot; in pubs, one with holds and nudges |
Learn these first
RTP, volatility, max win and paytable. The feature terms are explained on slot mechanics.
More guides: How to play online slots, Online slot RTP explained and Online slot volatility explained.
Slot figures are developers' published defaults, each confirmed against two sources; a casino may run a lower RTP. Offer terms dated 5 October 2026. How we check. 18+. Free help: 0808 8020 133 or safer gambling.
Frequently asked questions
What does RTP mean?
Return to player.
What is a tumble?
Winners removed and replaced.
What is cash collect?
A collector gathers values on other symbols.
What is a scatter?
A symbol that triggers from any position.