A slot is a narrow notch or groove, such as one in a door, a keyway in machinery, or a slit for a coin in a vending machine. It may also refer to a position in a group, series, or sequence. The term is also used in electronic gaming machines to describe a particular position where a player can place bets or activate special features.

In football, a slot receiver is a wide receiver who primarily lines up in the middle of the field. This position has become increasingly important as offenses run more three-receiver sets, and as teams employ nickel and dime defenses that focus on targeting these receivers. Physically, slot receivers are shorter and faster than traditional wide receivers, and they often must have the ability to run complex routes that require quick elusion and evasion to beat defensive coverage.

A slot is also a type of computer processor connection, originally designed to make upgrading the CPU easier by allowing the removal and replacement of a complete processor instead of just the socket. Today, however, slots are more commonly found on motherboards as an expansion connector for components such as video cards, hard drives, and RAM. A slot may also be a specific opening in the wing or tail surface of an airplane, as with the aileron and flaps, to provide a smooth flow of air on the top surface of the wing. At very busy airports, slots are a way for airlines to schedule their flights to avoid excessive delays caused by too many airplanes trying to take off or land at the same time.