Slot Machine Terminology and Lingo

There's a lot to take in but we've got you covered


Slots are easy to play but when you get started on a game, you might come across some words you haven’t seen before. Our look at slot machine terminology explains some of the key terms you need to know, helping you understand how slots work.


This feature is also known as a cascade and it kicks in after you’ve completed a winning combination on certain games. When this happens, the winning symbols explode, crumble or otherwise disappear and new symbols replace them to create a second opportunity to win.

This feature only works in those slots where it’s mentioned in the rules. You’ll also see the exact details of how the avalanche works (it varies by game). For example, in some slots the number of consecutive cascades after a win is limited. In others you might earn a multiplier with each new avalanche.

We can see this feature on slots such as Gonzo’s Quest Megaways, where all winning symbols except wilds disappear and a multiplier is added to each win after an avalanche.

Bonus Features

This is one of the slot machine terms you’ll see a lot! Many of the current slots have some sort of bonus round on them, which gives you an additional way of winning on top of the base game.

These bonus features cover a variety of different mini-games, free spins, re-spins and other ways of winning. Check the game’s paytable to find out what exactly to expect from the bonus round.

Azteca Cash Collect is one of the slots to include various features, with a bonus wheel and a cash collect function among them. On the other hand, Book of Dead has a single feature: a free spins round.


Clusters are one of a few ways to complete a win with a group of symbols. Wins come when a number of similar symbols land next to each other on the reels.

You’ll typically need at least three matching symbols for a win, with the amount you win rising the bigger the cluster. The slot’s paytable tells you everything you need to know about the prizes you could win in this way.

It’s easy to find games with this feature as these slots usually have the word ‘cluster’ in their name. Cluster Tumble and Dragon’s Cluster Buster are just two examples.

Free Spins

Free spins are offered as a bonus round on many slots. This feature is triggered by getting a certain outcome on the main game, such as three scatter symbols appearing anywhere across the reels. The free spins round gives you a fixed number of spins and might also add extra features to the base game such as more wilds or a special multiplier on wins.

You might also see free spins mentioned as part of the bonuses given by casinos. This could be as a reward for new players who’ve just signed up or one of the promotions for existing players to use. These no-cost spins let you try to win without using your own funds (although it’s always worth bearing any wagering requirements in mind).


A slot jackpot is the main prize in a game. This can be a fixed amount or it may be a progressive jackpot that rises over time. Some jackpots are paid randomly while others are triggered when you get a certain combination of symbols, fill up a meter or achieve some other sort of goal – they vary from title to title, with different mechanics and images to fit different games.

Slots can also have several jackpots of varying levels on offer. This means that there are different conditions listed for claiming each of them and you can only win one of them on any spin.

The daily jackpot category on the Paddy Power site adds a twist to this, by offering three jackpots with prizes that need to be won every day, it’s a jackpot that may be won on any of the linked games such as Wolfkin and Sheep Gone Wild.


The Megaways engine was first introduced in 2015 and caused an immediate impact on the slots industry. Rather than a fixed set of reels and rows, this way of playing introduces a high degree of change and fluidity as the layout changes on every spin.

This means that the number of ways of winning varies randomly as you play. The first Megaways slots were released by the creator of this engine, Big Time Gaming, but we’ve since seen it licensed by other developers to update their games and produce new versions.


The prize for a winning combination is determined by the symbols that make it up. This can change if there’s a multiplier – that’s slot machine lingo for whether your payout will be multiplied by a certain figure.

There are several different situations in which a multiplier can be applied, depending on the game’s rules. These include wins during the free spins round, wins following several avalanches and wins that involve certain wild symbols.


Paylines are the lines across the reels where winning combos can be formed. The earliest slot machines had a single visible row of reels that wins could occur on, but as the technology advanced we began to see more rows appear and different ways of winning.

Some games have 10 paylines while others have 20, 50 and so on. In slots with variable paylines, you can choose how many paylines to play with.

The likes of cluster wins and Megaways games have changed this format by introducing other ways of winning instead of the traditional paylines. Wins are always paid automatically, so it’s up to you whether you look into this aspect or just start playing.


We’ve mentioned the paytable a few times already because it’s one of the most important slot machine words. This is shown as a screen or series of screens where all the rules, bonuses and potential payouts are listed.

As online slots have got more complex, the paytable has become ever more important. Developers have tried to keep it simple and easy to read while putting all the relevant information on it.

Progressive Jackpots

While we looked at jackpots earlier, it’s important to mention the differences found in progressive jackpots. Rather than a fixed prize, this jackpot rises with each stake placed in the game.

These jackpots can reach large sums before being won; when someone does win, the prize pot resets. Jackpot King slots are an example of a linked progressive jackpot that’s listed on several slots at once and can be won on any of them.


The games that you find on the Paddy Power site have been created by third-party providers. These are experienced game developers who regularly produce new slots taking into account current themes and the best emerging technology.

Among the developers on our site, you’ll find big names like Blueprint, IGT, Big Time Gaming and Pragmatic Play as well as emerging providers who have full UK licensing and carry out regular third-party testing on their games.


The reels are the vertical lines that symbols appear on. The first mechanical slots used three cylinders which each had various symbols printed on them. With online slots, there are many variations involving three, five, six or more reels.

The reels in online slots have evolved so that they don’t even look like reels in some cases. These games can have floating symbols that move up and down in different ways, although some slots stick to the traditional look with virtual reels that spin around.  

In other cases, games are set up on a grid basis, say a 7×7 or 8×8 grid. The presentation of these slots seems far removed from the classic slots approach but once you start playing you’ll discover that they include many of the features and ways of playing we’ve covered in this slot machine glossary.


These are among the most important slot symbols, and they work differently from the others. Scatters don’t need to fall across paylines, as you’ll get a payout if you get the required number of them anywhere on the screen.

Scatters carry out another function as they usually provide a way to earn free spins when you get a few of them following a spin. The rules then differ between slots, as some let you earn more free spins if you get scatters during the bonus round, but others don’t allow this.

The scatter is often one of the most recognizable symbols as part of the overall theme. For instance, Fishin’ Frenzy uses a fishing boat while Diamond Mine has a sack of gold and Wild Wild Riches features a leprechaun’s hat. Other slots have ‘bonus’ or ‘free spins’ written across the scatter.


The next of our slot machine phrases is possibly the most important, as the symbols are the images that fall into place on the reels and can create winning combos. Each symbol has a value or function attached to it that determines what happens when it lands.

The rise of themed slots in recent years means that the symbols now often fit a certain theme. Examples include Greek mythology in Wisdom of Athena, wildlife in Buffalo King Megaways and exploring ancient Egypt in Book of Dead.

Retro-style slots may include some of the symbols that have been popular since these games were first created, such as bells, fruits and bar symbols. Therefore, when choosing a slot to play you might want to take into account the visual aspect of the theme as well as the features and different ways of winning.

Ways to Win

The number of ways of winning needs to be mentioned in slot machine terminology. This is a variation on the payline and clusters that we looked at earlier, as it lets you see all of the different ways that a winning combination can be formed.

Increasing the number of ways of winning is an interesting feature you might come across when playing. This works by expanding the reels or unblocking certain positions as you progress. You don’t need to keep track of the number of ways you can win, as it’s all done automatically on your behalf.


The wild acts as a sort of joker by replacing others to complete winning lines. This function has been expanded by some providers adding expanding wilds, sticky wilds and walking wilds to add variety.

Some slots will have a wild that is simply the word “WILD”. Others add an instantly recognizable and eye-catching image such as the gold coin featuring a leprechaun on Rainbow Riches or the image of the God Horus on Eye of Horus.


What are the common terms used in slot machines?

Terms such as reels, paylines and free spins are among those you’ll discover as you play these games. Thankfully, there’s nothing to stop you from starting to play and learning this lingo as you go, if you prefer.

How do I understand slot machine lingo?

Our list of useful slot machine words and terms tells you everything you need to know about playing these games. You’ll soon understand how they work and can start playing when you choose.

What are the myths and misconceptions about slot machines?

Many myths about slots have been created over the years, with some players believing that they can influence the outcome or that the games are somehow rigged. However, slots are simple games of chance whose outcome you can’t influence.

What do you think?