A surname.

(informal) Short for situation.

(intransitive, copulative, of a person) To be in a position in which the upper body is upright and supported by the buttocks. / (intransitive, of a person) To move oneself into such a position.

(mining) Subsidence of the roof of a coal mine. / (rare, Buddhism) An event, usually lasting one full day or more, where the primary goal is to sit in meditation.

To attend a private meeting or class without participating.

(idiomatic) shove it up your ass (up yours) or back off. / Used other than figuratively or idiomatically: see sit on, sit, on, it.

A peaceful form of protest in which people occupy an area and refuse to leave.

Designed to be sat in.

(idiomatic) To substitute; to take somebody's place.

(idiomatic) To attend a class, educational presentation, meeting, etc. for one time, as a visitor. / (music) To take part in a group musical performance, especially a jazz session, as a temporary guest.