A narrow notch, groove, or opening, as a keyway in machinery or a slit for a coin in a vending machine. Also, a position in a group, series, sequence, or plan: The new program got a slot on the broadcasting schedule.

A computer slot is a place on a motherboard where expansion cards can be installed. It can be referred to as an ISA, PCI, or AGP slot. In the United States, the term slot is sometimes used to refer to a specific time period in which an airport can receive clearance for takeoffs or landings, as part of an overall system of authorization and coordination called slots.

In football, a player who is assigned to cover a particular receiver on offense is known as a slot corner or nickel back. This is a difficult position to play, because the slot receiver catches passes all over the field and requires a quick and agile defender. Often, the slot corner is matched up against a linebacker, which can make the game very tactical and reduce its reliance on individual skill.

A slot is a dynamic container that either waits for content (a passive slot) or calls out to it (an active slot). Slots and scenarios work in tandem with each other, with scenarios referring to a repository item or specifying the contents of a slot, and renderers describing how the contents should be presented on a page.