(UK, slang, euphemistic, humorous) To menstruate; to be on one's period.

(informal) To be in a casual romantic relationship. / (informal, usually with "for") To have a crush on, or a soft spot for, someone.

(intransitive) To reach an end.

present participle of have someone on

(idiomatic) To have a weakness for something.

(idiomatic) To have endurance; to have prospects to exist or go on for a long time. / (nautical) To have speed. / Used other than figuratively or idiomatically: see have, legs.

(dated, chiefly imperative) take care; be on one's guard

(informal) To be concerned or involved in.

To engage in a romantic or sexual relationship while being married.

present participle of have an affair