Any act involving sexual stimulation.

To take action on the basis of information received or deduced.

(Catholicism) Vaginal intercourse between a married couple.

(pharmacology) Having a pharmaceutical effect principally in the short term.

(linguistics) An act carried out by speech, such as promising, ordering, greeting, warning, inviting and congratulating.

(pharmacology) Having a pharmaceutical effect principally in the long term.

present participle of act up

simple past tense and past participle of act up

(entertainment) A performance that involves balancing things precariously and suspensefully. / (figuratively, idiomatic) An effort to manage many conflicting or competing items or interests.

An impulsive act lacking motive.