act(noun)

something done

Running away is an act of cowardice; He committed many cruel acts.

act(verb)

to do something

It's time the government acted to lower taxes.

act(noun)

(often with capital) a law

Acts of Parliament.

act(verb)

to behave

He acted foolishly at the meeting.

act(noun)

a section of a play

`Hamlet' has five acts.

act(verb)

to perform (a part) in a play

He has acted (the part of Romeo) in many theatres; I thought he was dying, but he was only acting (= pretending).

act(noun)

an entertainment

an act called `The Smith Family'.