A narrow notch, groove, or slit, especially one for receiving something, as a coin in a slot machine or an envelope in an airmail box. Also, a position in a group or series: Her TV show is scheduled in the eight-o’clock slot on Thursdays. To place or fit into a slot: He slotted the piece of wood easily into the groove. These example sentences are selected automatically from various online sources to reflect current usage of the word’slot.’ Views expressed in these examples do not represent the opinions of Merriam-Webster or its editors. Send us feedback.

A machine that accepts coins or paper tickets with barcodes for cash redemption. Also, a machine with multiple reels where winning combinations occur when the symbols line up on a payline. Usually, the more symbols a player bets on a spin, the higher the payout.

Charles Fey’s 1931 mechanical slot machine allowed automatic payouts, replaced the poker symbols with diamonds, spades, horseshoes, hearts, and liberty bells, and had three reels. The latter change significantly increased the chances of aligning three liberty bells on a payline, earning the name “slot machine.” The electronic slot machines that followed had more than 22 positions on each reel, allowing many more possible combinations.

In addition, the random number generators used in modern slots make it very difficult to predict when a jackpot will be paid. The “hold” (the percentage of the total bet that the machine keeps) is also a major consideration, as increasing it decreases the amount of time players spend on the machine. This is not a controversial viewpoint, but some players have criticized increased hold for degrading the overall experience and preventing them from leaving the casino while they still have money in their wallets.