Act

/ækt/

Meaning & Definition

noun
a deed or a performance; something that is done or performed.
His act of kindness was appreciated by everyone.
a specific action or series of actions.
The first act of the play was very engaging.
a legal document or legislation.
The government passed a new act to protect the environment.
verb
to do something; to perform a function or action.
She decided to act on her instincts and apply for the job.
to take action in order to achieve a particular result.
The committee must act quickly to address the issues.
to behave in a specified way.
He tried to act mature in front of his parents.

Etymology

Late Middle English: from Latin 'actus', meaning 'a doing, a driving'.

Common Phrases and Expressions

act up
to misbehave or cause trouble.
act out
to express feelings through behavior rather than words.
put on an act
to pretend to be something one is not.

Related Words

action
the fact or process of doing something.
activity
a condition in which things are happening or being done.
actor
a person whose profession is acting on the stage, in movies, or on television.

Slang Meanings

to behave in a certain way, especially when trying to impress others.
He was just acting all cool at the party.
to fake a feeling or behavior.
Don't act like you know everything.