Online Slots Terminology

online slots dictionary

There are a ton of different terms in the online slots world that you may not know, and here we break them down into easy-to-learn categories.

RTP Percentage

RTP percentage means return to player percentage. This is the percent of all bets that are returned to the player on average. With a slot that has an RTP of 98 percent, for example, $98 out of every $100 wagered on it is paid out in prizes. The remaining $2, or 2 percent in this case, is what the house takes as their advantage. The lower the RTP, the better your chances of winning in a given session.


Paylines are the lines on the reels where symbols can line up to create winning combinations. Classic slots often have one, three or five, but video slots more frequently have 20 or more. Your bet size per spin is often considered the sum of smaller, individual bets on each payline.

Bonus Feature

A bonus feature is any aspect of the game that goes beyond the normal gameplay. Free spins, pick a box and instant win features are examples of bonus features. They are almost always used as a way to give players extra value that they wouldn’t have received from the regular pay table.

Classic Slots

Classic slots are three-reel games that typically have between one and five paylines. They almost always have one or three rows of symbols, and they’re based on the fruit machines from the early- and mid-1900s. Gameplay on these titles will usually be medium- or high-volatility, and they are limited in the bonus features available, in part because of the limited amount of screen real estate.

Video Slots

Video slots are usually five-reel games, though some have four, and some have six or more reels. They are based on land-based slot motifs that used video screens to allow for more ways to win and more options for bonus features. They often focus more on features and great graphics than their classic cousins as well.

Hot Slot Machine

A hot slot machine is based on this idea that a slot has been paying out a lot over recent history. The opposite of this is a cold machine, which would mean it hasn’t been paying off much recently.

Loose Slot

A loose slot is essentially a game with a high RTP percentage, so it pays out better than average. This is the opposite of a tight slot, which would be a game with a lower RTP percentage and a higher house advantage that doesn’t pay out as well.


Cashback is a type of promotion that gives you back either a portion of your deposit or a portion of net losses over a given period of time. In the online casino world, these deals are most commonly associated with online slots.

Bonus Money

Whenever you take advantage of an online casino bonus, your balance is often broken up into two parts: real money and bonus money. While you can make wagers with your bonus money, it’s frequently the case that you can’t actually cash it out, though you can cash out your winnings from playing with the bonus money.

Gamble Feature

A gamble feature is a feature found on a lot of slots that give you a chance to play a double-or-nothing or quadruple-or-nothing game with your winnings at the end of a winning spin. These features are almost always completely fair with no additional house advantage, and they often incorporate a virtual deck of cards as the randomizing agent.

Auto-Play Feature

An auto-play feature gives you an option to have the spin button press itself automatically for hands-free play. You get a ton of options on how this feature can work in terms of speed, how many spins to do before stopping, whether it should stop on big wins and features, etc. There’s plenty of customization with this type of feature so that players can make it work exactly how they would if they were physically pressing the spin button.


Pokie is an Australian term for video slot, and it comes from the original usage for video poker machines. It expanded to include other types of video machines, largely video slots, and is used in that area of the world to refer to online slots as a whole these days.

Fruit Machines

Fruit machines are three-reel, classic slots that have fruit-based motifs. The original three-reel slots used fruit motifs as a part of a semi-elaborate plan to get around gambling laws at the time. They did this by having prizes be different flavors of gum, and the flavor that you would win would be based on the type of fruit that you lined up to create the winning combination.

Win Multiplier

Multipliers in slots essentially multiply your winning amount by some value. They show up in a lot of different ways, but they all work the same by giving you a larger payout than you would otherwise get. Win multipliers are a common theme in free spin bonus features as a simple way to give more value during those spins than players would get during normal gameplay.


There are people who stream their online casino sessions online via video and audio feeds, and RIP in this context just means that the player has went bust. It’s hardly ever used in general outside of video streaming situations like this.

Ding Ding

Similar to RIP, ding ding is a phrase used by online casino streamers to point out when they have won big. It’s basically a way to allow viewers who are tuning in to know that a big win just happened without having to explain it over and over.

Random Number Generator

A random number generator is a part of a computer program that randomly chooses results for online gambling games, including slots. It’s important that there are sources of randomness used that cannot be tampered with in meaningful ways and that the results are actually random to make sure that the games are fair. It’s also important that no one is allowed access to manipulate or change the random number generator as well, which are things covered by reputable licensing jurisdictions.

Pay Table

The pay table for an online slot is what lists out each of the available prizes and the winning combinations that award them. It also includes details about the bonus features, how to trigger them and how the paylines work. It may also include other information about the game like a backstory as well.

Progressive Jackpot

Progressive jackpots work differently than regular jackpots because they aren’t tied to a static value. Instead, they start off at a certain seed value, and then they increase in value over time as a small piece of each bet on the game is added directly to the jackpot. Whenever the jackpot is won, the player gets paid out the current value of the pot, which is normally displayed somewhere easy to see on the game itself, and the jackpot size resets to the seed value.

Random Jackpot

A random jackpot can be a progressive jackpot or a normal, static jackpot. In either case, the idea is that it’s awarded at random on any given spin instead of being tied to a particular winning combination. A lot of progressives are like this, and the Real Series of slots by Realtime Gaming in particular is known for having a lot of random jackpots.


Reels are typically the vertical columns that virtually spin when playing a classic or video slot. They are based on the idea of actual mechanical reels that spun in the days of the earliest slots. In more modern online slots, the definition of reel has changed a bit since each individual spot on a game can actually be controlled by a different reel in some cases, and this allows for things like vertical paylines that weren’t an option with mechanical slots.

Scatter Symbols

A scatter symbol is a symbol that pays out according to how many you see on the screen, and they don’t have to be located on a specific payline to win. However, there are left-to-right scatters that have to appear on consecutive reels from left-to-right to pay, though their positions on those reels do not matter. These left-to-right scatters are the basis of slots with the “all-ways” format.

All-Ways Slots

An all-ways slot uses a different approach to paylines than usual. Instead of having specific paylines, all regular symbols work as left-to-right scatter symbols. The cost per spin is usually set at a specific number of coins instead of a set coin cost for each way to win. For the two most common examples, a 5×3 all-ways slot will have 243 ways to win, and a 5×4 all-ways slot will have 1,024 ways to win.


A spin is a round on a slot. It’s called a spin because the original slots had physical, mechanical reels that would spin until they came to a stop to determine any winning combinations. When you play on an online slot, virtual reels “spin” to create the same visual effect as the mechanical ones.

Wild Symbols

Wild symbols are symbols that substitute for any other symbol to help create extra winning combinations that you wouldn’t have received otherwise. Some wilds will substitute for any symbol, and some will only substitute for some symbols. They are generally designed so that you are awarded the largest possibly winning combination on a given payline, and they are a staple of modern video slots.

Variance or Volatility

Variance or volatility mean the same thing, and it has to do with the level of swings that you can expect to see within a game. A high-volatility or high-variance game will have larger swings that come more often, and a typical adjustment that players will make is to play with smaller bet sizes and longer sessions to smooth things out. Likewise, players might go with a larger bet size or shorter sessions with low-volatility and low-variance slots.

Power Spins

Also known as stop spins, this is a speed-based style of playing online slots that involves non-stop clicking of the spin button. The spin button typically functions as a stop button as well, so you can immediately stop the reels instead of waiting through the spinning animation, which doesn’t actually change anything about the results of the spin. Power spins, or stop spins, allow you to get in a lot more spins per minute as a result.

Winning Combinations

Winning combinations are sets of symbols that give you wins in a slot. If you get three cherries for a 5x win, that would be an example of a winning combination. The pay table is the chart that tells you about all of the possible winning combinations in a game. Likewise, a random jackpot is an example of a payout that does not require a winning combination to earn a prize.

Mega Ways

Mega Ways is a form of slot that you’ll see sometimes that uses a much larger area than the typical set of five reels and three rows. Something like seven reels with six rows is common, and they usually use an all-ways style to give you thousands of ways to get paid on each spin. It’s a high-action approach where wilds carry a lot more weight because of all of the extra winning combinations they can give you.

Near Miss

A near miss is when you come very close to hitting a winning combination. While it’s often used only to describe situations where a player comes close to hitting a bigger prize or jackpot, it technically includes any situation where a player was one symbol or one spot away from any kind of prize. This means it can include a wide range of situations under its technical definition, though it’s typically only used for coming close to winning big prizes and payouts.

Cold Slot Machine

A cold slot machine is one that doesn’t seem like it’s paying out much. This is the opposite of a hot slot machine, and it’s typically a superstitious sort of thing that doesn’t have any basis in the actual odds for the game.

Tight Slot

Similar to the concept of a cold slot, a tight slot is one that is set up to pay out a less-than-average percentage. In terms of RTP percentages, this could be something in the range of 94 percent and lower. Unlike a cold slot, which is only about what’s happened on a particular machine lately, the definition of a tight slot is about the payout percentage of the game itself.

Stacked Wild Symbols

Stacked wild symbols show up in a vertical row on a reel. The idea is that they can give you help on multiple paylines by covering one or more spots on the reel as a whole. They are a popular feature found in slots that are based on giving players a high hit-rate with lots of small and medium pays.

Sticky Wilds

Sticky wilds are another variation on the wild symbol. The way it works is that they will hold in place after the initial spin where they appear for at least one subsequent spin. Sometimes they will have a counter on them that tells the player how many spins are left for the sticky wild, and other times they will last for a set period of time, like to the end of a free spins bonus round. They are associated with high-volatility slots a majority of the time.

Expanding Wilds

An expanding wild symbol expands to cover more than one space whenever it lands somewhere on the reels. The most common case for this is that it will expand vertically in both directions to cover an entire reel in wilds, but there are several variations. Some may expand only in one direction vertically, and some will expand to create different types of patterns like an X pattern or a plus sign pattern.

Colossal Wilds

Colossal wilds are a type of wild symbol that covers more than the typical one-symbol area. They most often cover square areas of 2×2 or 3×3, and they are obviously a high source of value because of the huge winning combinations that they can help to produce. They may appear in other shapes as well, but squares are the most common by far.


If you’re in a bonus feature in an online slot, particularly if it’s a free spins feature, then re-triggering the feature means that you add on even more chances to win. If you need three scatters to get the feature in the first place, and then you get three scatters while you are playing your free spins, that’s an example of a common way to re-trigger a feature.

Coin Size/Coin Value

In many slots, betting is based on a certain number of coins per spin. A 20-payline slot might have you bet 20 coins per spin. To adjust your total bet size, you can adjust the size of the individual coins under this betting structure. Therefore, a coin size of $0.01 would produce a total bet size of $0.20 per spin, but a coin size of $0.05 would make the betting $1 per spin.

Max Bet

A max bet option in a slot can mean the absolute largest available bet size in the game as a whole, or it can mean that one single aspect of the betting is maximized. This usually refers to betting as many individual coins as possible, though it doesn’t necessarily mean that you’re using the largest coin size available.

Free Spins Feature

A free spins feature is the most common type of bonus feature you can find in the online slots world. This is a set of spins that you do not have to pay for, and they typically auto-play themselves out immediately after you win them. Your total win during the feature is accumulated, and then it’s announced to you at the end of the bonus round to give you an idea of the total amount of value you earned from it.


The collect option means that you take your winnings from a slot round and add them to your account balance. This is an important option whenever you have other choices of things you can do with your winnings, like re-wagering them in a gamble feature or another type of bonus feature, which is common in classic slots that have two or more sets of reels.