Slots Glossary for the 2020’s

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Slots Glossary

The slots world has definitely changed within the last decade or so. Unique bonuses and new formats, such as Megaways and Gigablox, have entered the gaming world.

These changes may leave you puzzled about new slots terms. And a slots glossary from five or 10 years ago isn’t of much help today.

List of Slot Machine Gambling Terms

The following glossary provides a mixture of old terms and ones that are more relevant to the 2020s. It covers some of the new concepts and bonuses with real money slots that have been introduced in recent years.

243 Ways

This type of slot offers 243 ways to win. It features an any-ways-pays engine along with a 5×3 grid (3x3x3x3x3 = 243).

1,024 Ways

This type of game provides 1,024 ways to win. It has an any-ways-pays engine along with a 5×4 grid (4x4x4x4x4 = 1,024)

Any Ways Pay

A slots engine that pays when matching symbols land in adjacent reels. Winning combinations usually must start in the first reel and move to the right. Any ways pays contrast payline slots, which only pay when matching symbols land in paylines.


This option makes the reels spin automatically with your preferred betting options. Depending upon the slot, you can use autoplay for up to 50, 100, 1,000, or infinity spins.

Bet Max

The Bet Max option automatically turns a game’s stake size to the highest setting.

Bonus Round

Most slots feature bonuses, such as free spins or a pick’em round. You normally need to land three or more scatter symbols to trigger a bonus.

“Book of” Slot

The term Book of describes a variety of Egyptian-themed slots that offer the same setup (5 reels, 10 paylines) and bonuses (free spins, expanding wilds). Book of Dead, Book of Horus, and Book of Ra are all examples of these games.

Cascading Reels

This feature causes symbols from winning combinations to disappear. Meanwhile, symbols from above fall into the vacant places. Cascading reels allow for more payouts and continue until no more wins are possible.


Many land-based and online casinos offer cashback (e.g. 0.1%) to slots players. Cashback is based on a player’s total betting volume (e.g. $1,000 x 0.001 = $1 cashback).

Classic Slot

This term normally describes a slot with just three reels and one payline. However, some gamblers use it to describe any three-reel game.

Coins Per Line

Some slots provide the option to bet more than one coin per payline. For example, you may be able to put between 1 and 10 coins on a line.

Cluster Pays

Payouts that form through clusters of touching symbols. Cluster pays can form vertically, horizontally, or a combination of both.

Expanding Wild Symbol

A wild symbol that expands to fill its respective reel.


Feature Buy (a.k.a. Bonus Buy)

First introduced in White Rabbit Megaways, feature buy lets you automatically trigger the bonus round. You need to pay a certain multiple of your stake (e.g. 100x) to use bonus buy.

Fixed Jackpot

A jackpot that’s fixed at a specific value. The fixed value can be either a dollar amount (e.g. $10,000) or a stake size (e.g. 10,000x the stake).

Free Spins (Bonus Round)

This bonus provides free spins that you can use to make extra money. Free spins are often accompanied by one or more bonuses, such as expanding wilds or a win multiplier.

Free Spins Bonus

Many online casinos offer deposit or no-deposit bonuses that contain free spins. For example, you might deposit $20 and get 30 free spins for use on any slots game. This term shouldn’t be confused with a free spins bonus round (covered above).

Gamble Option

Slots with the gamble option let you risk your current payout for a larger one. For instance, you might choose a card color (red or black) to double your payout. Guess wrong, though, and you’ll lose the payout being risked.


Developed by Yggdrasil and debuted in Lucky Neko, the Gigablox engine drops symbols ranging from 2×2 to 6×6 in size.

Grid Slot

These slots offer cluster pays and typically feature a grid ranging from 6×6 to 8×8.

Hit Rate

The percentage of spins that result in at least one winning combination (e.g. 25% hit rate).


Available in fruit machines, the hold option lets you hold a specific reel in place.

Info Screen

A second screen (usually marked “i”) that shows the pay table, game rules, bonus rules, RTP, and possibly more.

Linked Reels

Two or more reels that fill up with the exact same symbol. NetEnt is known for making slots with linked reels, such as Twin Spin.

Loose Slot

A slot that’s particularly generous with payouts.

Losses Disguised as Wins (LDWs)

A win that’s worth less than the stake. For example, a $0.10 payout on a $1 spin still sees you lose $0.90 overall.


Invented by Big Time Gaming, Megaquads slots start with four separate 4×4 grids. The grids can merge into an 8×8 grid and offer up to 16,777,216 ways.

Maximum Win

The highest payout available in a given game. The max win is usually listed as a multiple of the stake (e.g. 5,000x the stake).

Wager Money

Mechanical Slot

Up until the 1970s, many slot machines operated through mechanical reels.


Another Big Time Gaming invention, Megaways slots offer a variable number of symbols in each reel. A common Megaways setup includes 6 reels with each reel holding 2-7 symbols. When all reels are at max height, such a game offers 117,649 ways (7x7x7x7x7x7).

Multiplier Wild

A wild symbol that comes with a multiplier attached. A 5x multiplier wild, for example, will multiply any win that it helps form by 5x. If two or more of these wilds appear in a win, their multipliers will either add together or multiply each other.

Mystery Symbol

Usually denoted by a question mark, mystery symbols will all change into the same symbol at the end of a round.


In the past, nudging referred to moving a specific reel one or more positions on a fruit machine. The more-modern definition, though, alludes to when a symbol nudges one or more positions to become a stacked symbol.

One-Armed Bandit

A dated nickname that describes a slot machine’s tendency to quickly take players’ money. The “one armed” part refers to how old slot machines featured pull levers.


A line where winning combinations can form. For example, a 20-line slot features 20 paylines where wins can land.

Payout Percentage

See return to player (RTP).

Pay Table

A list of the different payouts that each symbol offers. The pay table is commonly found in the info (“i”) section.

Pick’em Round

A bonus where you select one or more onscreen options to reveal prizes.

Progressive Jackpot

This type of jackpot takes a small percentage of each bet. It continues growing in this manner until it’s finally won. The software developer then reseeds the progressive jackpot at a certain amount.

Random Number Generator (RNG)

A program that cycles through random number sequences to determine slots results. It begins working immediately after you push “Spin.”

Return to Player (RTP)

The percentage of bets that a slot machine pays back to players. A game with 96% RTP, for example, will pay back $96 on every $100 wagered over time.


This term describes when developers clone the core elements of a specific game. They’ll then apply these core elements to other games, with only the theme separating one from another.


A bonus that provides free respins with one or more symbols held in place (a.k.a. sticky). Oftentimes, either wild or scatter symbols will remain sticky during respins.

Rolling Reels

Microgaming’s term for cascading reels. Jungle Jim El Dorado popularized the name rolling reels.

Scatter Payout

A special payout that’s awarded when a certain amount of scatter symbols land on the reels.

Scatter Symbol

Special symbol that can pay and/or trigger bonuses from anywhere on the reels. It doesn’t need to appear in a payline or adjacent reel to deliver a bonus and/or payout. Oftentimes, three scatter symbols will trigger a bonus round.

Second-Screen Bonus

A bonus round that takes place on a second screen separate from the reels. Pick’em rounds are common second-screen bonuses.

Split Symbol

A single position that contains two or more symbols.

Spreading Wild

This wild symbol can spread to other positions and create more wilds.


Stacked Symbol

This symbol fills up its respective reel.

Stacked Wild

A wild symbol that fills its respective reel.


The total amount of money that you bet on a spin. If you wager $0.10 on 20 paylines, then your total stake will be $2.

Sticky Wild

This wild symbol remains on the reels for multiple spins.

Synced Reels

See linked reels.

Ticket In/Ticket Out (TITO)

Used in land-based casinos, this system sees players receive payouts in ticket form. They can insert the ticket back into any machine and receive credits. TITO replaced the old system, which involved players inserting nickels, dimes, and quarters into machines.

Tight Slot

A game that’s being stingy with payouts.

Tumbling Reels

Another term for cascading reels.

Video Slot

Slot machine that runs through computer technology instead of mechanical reels. Every modern slot is a video slot machine.


Developed by No Limit City, the xWays engine sees certain symbols split into 2 or 3 symbols. In the process, xWays expands the number of ways to win.

Walking Wilds

Sticky wild symbols that move one reel over after every spin. They remain sticky until moving off the last remaining reel.

Wide-Area Progressive Jackpot

This type of progressive jackpot can be hit in multiple land-based casinos. Megabucks is the most-famous example of a wide-area progressive jackpot.

Win Multiplier

A multiplier that boosts wins. In some games, the win multiplier increases by 1x with each cascading/tumbling win.

Winning Combination

A combination of matching symbols that produce a win.

Wild Symbol

This special symbol substitutes for other symbols to help form winning combinations.


If you compare this current slot machine glossary to one published 10 years ago, you’re going to find some terms that are the same. But you’re also going to find many new terms.

The slots world is constantly evolving and changing. Make sure that you stay up to date with all of the new terms.

Michael Stevens

Michael Stevens has been researching and writing topics involving the gambling industry for well over a decade now and is considered an expert on all things casino and sports betting. Michael has been writing for since early 2016. ...

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