A slot is a container for dynamic items on a Web page. It is either passive or active and it waits for content (a passive slot) or it calls out for content to be inserted into it by a targeter (an active slot). The contents of a slot are dictated by a scenario that uses an Add Items to Slot action or by a targeter to fill the slot with content. The slot is then displayed by a renderer to the page’s viewers.

A position in a group, series, or sequence. For example, visitors can book time slots for a visit to the exhibit.

In a slot machine, a player inserts cash or, in “ticket-in, ticket-out” machines, a paper ticket with a barcode into a designated slot, which activates reels that display symbols. If the player matches a winning combination, they earn credits according to a pay table. Most slot games have a theme, and the symbols and bonus features are aligned with that theme.

The term slot is also used for an opening in the wing or tail surface of an airplane to accommodate a control device, such as an airfoil, flap, or ailerons. The word is derived from the Latin esclusiva, meaning “to cut out,” and in this context it refers to an opening made by cutting or punching into a flat surface. From Middle English slit, from Old French escluse, from Proto-Germanic *slutila (“bolt, bar, lock, castle”), related to Latin sluscia “lock”.