One mechanic, three names: that is the normal state of slot terminology, because studios keep coining fresh labels for familiar ideas. This reference sorts the vocabulary by job rather than by alphabet, so terms that do similar work sit next to each other. Each entry gives a short plain-English meaning and, where one exists, a game in the SlotSpecs database that shows it, with the detail drawn from that game’s published rules. For anything missing here, the help screen inside the game has the final word, since UK standards require rules to be accurate and understandable before play begins.

Spec sheet terms

RTP. Return to player: the share of stakes a game is designed to pay back over the long run. The RTP and volatility guide covers it in depth.

Volatility. The degree to which that return is split between small regular results and big rare ones.

Hit frequency. The proportion of spins that pay anything at all. For Sweet Bonanza 2500 the published figure is roughly 1 in 2.33 spins.

Max win. The stated ceiling for one round, given as a multiple of the stake. Gates of Olympus 2500 stops at 25,000x.

Losses disguised as wins. A research label for payouts below the stake that are dressed up with winning sounds or animation. A 2010 study by Dixon and colleagues found players’ bodies responded to them much as to genuine wins. From October 2021 the Gambling Commission prohibited such celebrations in UK-licensed online slots.

How wins are counted

Payline. A set route over the reels along which identical symbols have to line up. Big Bass Splash runs 10 that are fixed.

Both-ways pays. A line system paying left to right as well as right to left. Lucky Pharoah has 10 lines that pay in both directions.

Ways. Matching symbols on neighbouring reels win regardless of row. Huff N’ Even More Puff Grand runs 243 of them.

Megaways. The Big Time Gaming mechanic introduced in 2016, where reel heights shift on each spin to give as many as 117,649 ways. There is more in the Megaways explainer.

Anywhere pays. Identical symbols count in any position, typically from eight upwards. Sweet Bonanza 2500 applies this to a 6×5 grid.

Cluster pays. Wins come from groups of identical symbols that touch. Sugar Rush 1000 needs five or more together on its 7×7 grid.

Grid mechanics

Tumble, also called cascade. Paid symbols vanish and replacements drop in, so one spin can produce a chain of wins.

CollectR. The ELK Studios system behind Pirots 5, in which collector birds pick up matching gems on a 6×6 grid capable of growing to 8×8.

Grid expansion. The play area gets bigger during a spin or feature, such as the Pirots 5 jump to 8×8.

Nudge. After landing, a reel or symbol shifts by one or more positions. Fortune Garuda 500 has both Nudge and Nudge Wild on its special reel.

Wild symbols and their variations

Wild. Stands in for other paying symbols to finish a win, though it usually cannot replace a scatter. In Cleopatra the wild doubles every win it helps create.

Expanding wild. Grows to cover its entire reel after landing. In Eye of Horus, Horus spreads to fill reels 2, 3 and 4.

Multiplier wild. Carries a value that is applied to any win it joins. The Dog House Megaways 1000 puts values from 1x to 1,000x on wilds across reels 2 to 5.

Sticky wild. Holds its position across several spins, typically until a bonus round ends. One of the free spins modes in The Dog House Megaways 1000 is built on Sticky Wilds.

Random wild. Placed on the grid by the game instead of landing on its own. In the Random Wilds mode of that same game, up to six appear each spin and are removed afterwards.

Stacked wild. Lands as a tall column of wilds on a single reel. White Orchid stacks them on reels 2 to 5.

Collector wild. Picks up the values printed on other symbols. During free spins the fisherman in Big Bass Splash gathers fish values, and Fishin Frenzy uses a fisherman wild the same way in its free games.

Trigger symbols

Scatter. Pays or starts a feature in any position, no line required. Cleopatra’s Sphinx scatter pays against the total stake, and three or more begin free spins.

Reel-limited scatter. Can only appear on particular reels. The flower scatter in White Orchid shows up on reel 3 and nowhere else.

Super scatter. A scarcer scatter that opens a stronger bonus. Super Scatters in The Dog House Megaways 1000 lead to two Super Bonus levels.

Bonus symbol. A broad name for any symbol that sets off a feature. In Golden Winner, three, four or five Bonus scatters give 10, 15 or 20 free spins.

Multiplier vocabulary

Multiplier. A factor applied to a win. The important question is how a game combines several of them, which differs from title to title.

Additive multipliers. The values are summed, so 2x with 3x makes 5x.

Multiplicative multipliers. The values are multiplied. In The Dog House Megaways 1000, wilds of 5x and 10x on one way produce 50x rather than 15x.

Bomb or orb. A symbol holding a value that is gathered up and applied once a tumble sequence ends. Pragmatic Play’s Sweet Bonanza 2500 page lists candy bombs worth up to 2,500x during free spins, summed and then applied to the total win.

Position multiplier. Tied to a grid square rather than a symbol. In Sugar Rush 1000 a square’s multiplier doubles with each repeat win there, up to x1,024. In Duck Hunters each square holds a multiplier that doubles on further hits, reaching x8192.

Multiplier reel. A standalone reel whose value is applied to a line win. On Fortune Garuda 500 that reel ranges from 1x to 500x.

Progressive multiplier. Climbs in stages through a feature. Golden Winner advances along a 12-step trail that lifts its multiplier as high as 10x.

Inside the bonus round

Free spins. Rounds that take no fresh stake, normally unlocked by scatters. Wins are usually priced at the stake of the spin that triggered them.

Retrigger. More scatters during free spins add extra spins. Cleopatra’s round can extend to as many as 180 spins.

Progress ladder. Rewards for reaching milestones within the round. In Big Bass Splash, collecting fishermen lifts the multiplier to 2x, then 3x, then 10x.

Mode choice. After triggering, the player selects which version of the bonus to play, for example sticky or random wilds in The Dog House Megaways 1000.

Wheel. A spinning wheel settles which bonus or prize is awarded. Huff N’ Even More Puff Grand has three tiers: Wheel, Super Wheel and Ultra Wheel.

Hold and respin. Special symbols lock while respins play out, and each fresh coin restores the counter. The Cursed Temple coin game in Pirots 5 uses an 8×8 grid and returns to three respins whenever coins land.

Win conversion. A win is traded for a feature. In Lucky Pharoah, any win of 4x the bet or above can be swapped for Power Spins.

Symbol upgrade. A symbol is improved for the remainder of the round. Each Horus wild in the Eye of Horus free games upgrades one picture symbol.

Ante bet. A raised per-spin stake that improves the odds of reaching the bonus. Gates of Olympus 2500 offers three levels. The name changes between studios: Golden Winner’s Fortune Bet, offered in some jurisdictions, adds 50% to the spin cost and uses stacked Bonus scatters to make free spins likelier.

Super spins. Costly base spins that come with guaranteed modifiers, for example a multiplier on every spin. Sweet Bonanza 2500 has two tiers, and free spins cannot be triggered while they are active.

Feature buy. A fixed multiple of the stake paid to go straight into a bonus. Whether it is offered depends on jurisdiction; the feature purchase guide has the details.

X-iter. The ELK Studios brand for its set of purchase and boosted-stake options, found in Pirots 5.

Gamble option. A chance to stake a win on a guess, a card colour for example. Certain builds of Golden Winner and Eye of Horus include one, depending on jurisdiction.

Glossary questions

How does a wild differ from a scatter?

A wild replaces other symbols to complete wins. A scatter pays or starts a feature in any position and generally cannot be replaced by a wild.

Is a sticky wild just another word for an expanding wild?

No. Sticky wilds stay put over several spins, while expanding wilds fill their reel on the spin they land.

When several multiplier wilds land, are they always multiplied?

No. Some games add the values and others multiply them. The help screen states which, and the gap between the two can be big.

What is meant by anywhere pays?

Identical symbols count in any position on the grid, usually from eight up, with no lines or neighbouring reels needed.

Are ante bets and feature buys the same?

No. An ante bet makes every spin dearer so the bonus comes more often. A feature buy is a set payment that starts the bonus immediately.

How can I confirm how a feature works in one particular game?

Open the game’s info screen, or read the review on that game’s SlotSpecs page.

Sources