If you are looking for the most comprehensive glossary of modern-day slot machine terms then you are in the right place. When it comes to slot machines there is so much outdated terminology that it does not even make sense most of the time. Slots have come a long way since the twentieth century, and as slot enthusiasts, we have decided to put together a definitive list of current slot machine explanations that users can associate with their gameplay.

This is an up-to-the-minute list of definitions that will suit new and seasoned UK slots sites players alike. The list of definitions below will allow you to understand slot reviews without batting an eyelid. To make the reference even easier, we have listed it in alphabetical order.


Key Slot Machine Definitions

Key Slot Machine Definitions

234 Ways to Win – Slot games that do not restrict to one payline to determine winners are called 243 Ways to Win. It’s a winning combination as long as they are adjacent from left to right or right to left.


1,024 Ways to Win – It’s similar to a 234 ways to win the game but with an extra row of symbols. The five reels with four columns create an expanding amount of new paying combos.


3D Video Slots – Those video slots that have heavy 3D animation graphics. It provides an added depth to gameplay by making the symbols look realistic upon hitting a payline.


3-Reel – It is a classic slot machine, which has 3 reels with spinning columns of symbols.


5-Reel – It is a modern layout slot machine with five spinning columns of symbols. It has become the new standard for online slots.


6-Reel – These slot machines are new additions, with an extra column of spinning symbols. Games in this category mostly have additional features.


Action or Play – When a player puts the club card in the slot machine, it starts tracking the playing time. This term also refers to the total amount of money wagered (including the amounts won or lost during a session) on a slot machine. Casino game owners use this information for bonus offers while clearing wagering and rollover requirements.


Active Payline – It’s the one that has a bet placed on it. It is “turned on” when it pays a prize on landing a winning combination. Many slot machines let players activate or deactivate a payline to adjust the wager.


Annuity Winner – When instead of a lump sum, the jackpot gets paid in instalments over many years.


Bar – Any one of three symbols that encompass a ‘Bar line’ on a payline. A ‘Bar is a horizontal strip that states the message; ‘Bar.’ Three horizontal bars typically pay the highest, followed by two and then one.

Base game – The regular state of the game, when no features are in play.

Betways/Paylines/Ways to Win – The number of lines, or ways, that players can bet on to afford a win on the slots.

Basic Slots – Retro-style slots with one single payline and a static jackpot, that does not change like progressive jackpots.


Bet Min – It refers to the minimum number of credits which can be bet on a slot machine in each spin.


Betting Units or Credits – It is the conversion of real money into the denomination that a slot machine uses for playing.


Bet One – It refers to only bet one unit/credit per spin of the slot machine.


Big Bertha Slot Machine – A type of land-based, large slot machine, placed in casinos as attention getters


Big Hit or Big Win – This term refers to the top price offered by the slot – top payout, or jackpot.


Bonus Multiplier Slot Machines – It refers to those slot machines offering larger jackpots to lure players to bet the maximum number of credits.


Bonus Multiplier or Bonus Modifier – It is a symbol or series of symbols that multiply the winning amount like two times (2X), three times (3X), and so on.


Branded Slots – It’s an online themed based slot game with famous movies or TV programmes like Wheel of Fortune Slots or Lord of the Rings slots. It contains added features and attractive gameplay graphics.


Buy A Pay – Some games have this feature to place a bigger wager that allows a player to compete for the top prize or jackpot.


Buy A Feature – Similar to buy-a-pay, it allows players to activate the restricted features of some slot games.


Cascading Symbols – A winning combination on the slots that leads to the removal of all winning symbols, making space for new symbols and a redetermination of payouts.

Chain Reaction – Cascading reels progress so that one win follows another consecutively. Chain reactions occur until a player strikes no more winning combos on the slots.

Classic Slots – A slot machine that has been tailored to the specific requirements of a fruit slot machine. These slot machines typically incorporate fruits, bells, or Bars.

Coins – This is the value of each coin. For instance, a player can wager a minimum of 1c per payline. The coin size is 1c in this example.

Candle – It’s the light on top of a slot machine. A player can use it to call over an employee in the case of an issue, or hitting the jackpot


Cashback – It’s a bonus given in the form of monetary gains to regular players like a part of some loyalty programme.


Casino Bonus – Most online casinos offer it to the new player as a welcome bonus.


Certified Slots – It refers to those slot machines promoted by casinos that guarantee a payout of 98%-100%.


Cash Out – It signifies to an action when a player converts the credits back into real money by using a cash-out button.


Coin In / Coin Out – This term refers to the number of credits both played by a player and paid out by the machine.


Coin Size or Denomination – It’s when size is used to amount each coin it’s worth – small as £0.01 or large as £100.


Coin Hopper – It refers to the container where the coins are available for payouts.


Coin Slot – It is a physical hole where you put your coins to fund the slot machine.


Cold Slots – A slot machine slang, for those which do not pay out very often


Comps – It refers to complimentary rewards or perks like free rooms and meals. In the case of online casinos, it means promotions/offers such as comp points.


Credit Meter – A visual meter displaying the number of credits in the machine at any given time


Demo Mode or Practice Mode – This feature allows playing a slot game, but one cannot win real money, and the balance does not carry over.


Doubles – It refers to the instance when symbols on the slot machines come up two or three at a time resulting in the double or triple winning amount.


Drops – A new feature in online slots, where symbols fall into place instead of spinning reels


Drop Bucket – The container where excess coins get diverted from the hopper to the base of slot machines


Expanding Wilds – When a ‘WILD’ symbol appears on the screen, it expands to cover the entire reel, forming larger chances of wins.


Feature – A special game on the slots that can incorporate various aspects such as free spins, bonus rounds, expanding wilds, and more.

Free Spin Feature – Winning free spins. This is usually accomplished by landing three or more scatters.

Fixed Value Slots – It’s the game where the betting amount and coin size is fixed.


Five Liner – This term refers to a slot game that contains 3-reels and players get the chance to win on up to five payout lines.


Fixed Jackpot – It’s a traditional payout in slot machines, where a player wins a set amount if they hit the jackpot combination.


Freeplay / Free-to-play – Those online slot games, where players get to play for free without risking money


Fruit Machine – A nickname for slot games in the UK, containing fruit symbols


Gigablox – Numerous icons join to form a larger symbol. The player has ample chances for huge wins.

Grid – The layout of a slots machine. For example, a 3×3 grid slot has 3 reels, or columns, and 3 rows.

Gamble – It’s a feature that allows a player to try and double the winnings on a spin.


Hammer A Machine – It’s slang for playing the same slot machine for a long time, attempting to win a progressive jackpot.


Hit and Run – A slang used for those players who try a slot for a few spins, and immediately abandon it if it fails to pay out any credits.


Hit Frequency – It’s a theoretical number that signifies how often to expect landing a winning combination.


Hold Percentage – Its the percentage of the total bets placed on a slot machine that is kept by the casino.


Hot Slots or Loose Slots – Those slot machines that payout often.


Jackpot – Self-explanatory. The maximum value that a player can win on a slot machine. Modern slots may have more than one jackpot, which means that there are numerous jackpots to be won.

Line Bet – It refers to the wagering amount on a single slot machine line.


Linked Progressive Jackpot – It refers to the network of progressive jackpot slots that linked across several casinos, contributing to the growing jackpot.


Max Bet – Also referred to as ‘Bet Max’ or maximum bet; refers to the maximum stake that a player can wager per spin.


Megaways – A slot machine with variable reels, where the number of symbols appearing on each reel changes with every spin.

Mystery Symbol – A symbol that converts into other symbols. A mystery symbol will modify during certain features, depending on the game.

Multiplier – It is an amount a winning spin multiplies (x2, x3, x4), thus increasing the amount of payout.


Nudge Slot – A slot machine which allows the player to move a key line up or down for creating a winning combination


One-armed Bandit – Old school slots machine developed in the 1900s. The slot machines in those times were based on three reels. A player could pull a lever to generate an outcome. Most people would probably associate these with Western saloons.

Paytable – A representation provided by the software developer that depicts the value of the payout for winning combinations on a slot machine.

Premiums- The highest paying icons on a slot paytable.

Payout – It refers to the amount won for getting a specific combination of symbols.


Penny Slots – These are low-stakes slot machines, set for a coin size of one cent.


Progressive Jackpot – Mostly, linked to multiple progressive slot machines or a network of online slot games with a jackpot that changes over time and grows with each spin.


Random Number Generator – Also referred to as RNG; this is a computer program that is integrated into slots and generates results that are completely random, ensuring fair gameplay.

RTP – Return to Player. This is expressed as a percentage and is the theoretical advantage that a player has over the slot machine or casino.

Reels – It’s the disc that spins inside the slot machine window with various symbols.


Slot Machines – A gambling machine that is operated by inserting funds and betting funds. Players can win an amount shown on the pay table. The monetary value of the amount won by players depends on the value of the coin size bet and the icons on the pay table.

Scatter – A symbol that initiates a bonus feature or random prize, depending on the slot. Three or more scatter icons will regularly result in a bonus round or free spins on popular slot machines.

Spin – An action that results in the slot machine initiating a spin. This can be done manually or through the ‘autoplay’ feature offered on many slot machines. When initiated manually, it involves hitting the ‘SPIN’ button on the slot machine.

Spin Booster – A relatively new feature that lets players gamble in an attempt to win additional spins or bonus games.

Symbol – An image that represents a specific value on the paytable.

Suits – 9, 10, J, Q, and Ace. Typically the lowest paying icons on a paytable. A player that lands 5 suits is usually less than impressed.

Stacked Wilds – An exciting feature that sees numerous Wild symbols on the same reel stacked on top of one another. Essentially, two or more wild symbols land on the reel of the slot machine.

Second Screen Bonus – Video slots machines offering a bonus feature, takes the player to a new window with a mini-game of a different format.


Short Pay – It’s a situation when a payout occurs partially due to insufficient coins in the machine. The player gets the rest physically from casino people.


Short Win – It’s slang for winning a jackpot with few spins.


Skill Bonus – A bonus feature to test the skill of a player in a mini-game, awarding a higher prize for better performance.


Slot Club or Player’s Club – It’s a casino promotion for regular players, where they offer prizes and rewards in exchange for playing.


Stacked Symbols – It’s a modern feature in online slots, where the same symbol covers most or all of the reels. Thus, increasing the odds of getting a winning combination.


Tight Slots – It refers to those machines which payout at a lower than expected rate.


Trail – It’s a bonus feature in some slot games, where players progress on a prize track, unlocking new awards.


Video Slots – A range of online slot machines offered by some of the world’s best software providers. These video slots have state-of-the-art graphics and next-level audio.

Variance – This term refers to the risk associated with a particular game.


Wild Symbol – A symbol that substitutes for all other icons. This symbol often does not substitute for the scatter symbol.

Winning Combination – Usually three or more symbols on an active payline. Some slots afford a win with less than three symbols.

Wide Area Progressive or WAP – It’s part of a network of slot machines in a wide area, linked to a common pot for winning the jackpot. Most online progressive jackpot slots are WAP.


Win-Both-Ways – It refers to a paying combination of paylines running left-to-right and right-to-left.


Zig-Zag – It is when a payline moves in a crooked across the rows and columns of the reels. Instead of going straight across the screen or diagonal, it creates multi-line payout slots.


Evolving Slot Terminology

Evolving Slot Terminology

The main thing to remember about slot machine terms is that they are always changing. Innovative developers like Big Time Gaming and Yggdrasil Gaming are constantly introducing us to new slot machine mechanics, and new terminology. This is why slot machines are so exciting. We have a curiosity for slots, which is why we curated the list above.

With the help of the above-listed glossary terminologies, and understanding what they really mean, would give you a slight advantage over the others. Remember that slot machines have a tendency to evolve at a rapid rate, so check back frequently if you do not understand the operator’s terminology or need clarity about a subject.

We are always here to help. Let us know if we missed something, we’re not robots.


amelia cassiday profile pictureAmelia Cassiday is an online bingo writer and player for the past 5 years. Her expertise and knowledge of the online bingo industry are utilised when covering the latest news and trends. Amelia particularly enjoys reviewing new bingo sites as well as writing detailed game guides. When offline, she can be found maintaining her garden and reading a good book at her home in Newcastle, UK.