Definition of “act” - English Dictionary

“act” in British English

See all translations

actverb

uk /ækt/ us /ækt/

act verb (DO SOMETHING)

B2 [ I ] to do something for a particular purpose or to solve a problem:

She acted without thinking.
Who is acting for/on behalf of (= who is representing) the defendant?
He never acts on other people's advice (= does what other people suggest).
Acting on impulse (= without thinking first) can get you into a lot of trouble.

More examples

  • You'll have to act fast or you will lose your chance.
  • It's very important to act now before the problem gets really serious.
  • The court decided that the companies acted illegally.
  • Despite what you think, I'm only acting in your best interests .

act verb (PERFORM)

B1 [ I or T ] to perform a part in a film, play, etc.:

Ellis Pike was chosen to act the part of the lawyer in the film.
Have you ever acted in a play before?
act the fool, martyr, etc.

to behave in a particular, usually bad, way:

Why are you always acting the fool?

More examples

  • Try to act confidently, even if you feel nervous.
  • She's married, but she doesn't act as if she is, if you see what I mean.
  • Abraham was able to act as interpreter for our group.
  • Stop acting the fool, I'm trying to talk to you.
  • The whole play was appallingly acted.

actnoun

uk /ækt/ us /ækt/

act noun (THING DONE)

B2 [ C ] something that you do:

The simple act of telling someone about a problem can help.
Primitive people regarded storms as an act of God.
artistic representations of the sexual act

More examples

  • His murder was an outrageous and barbarous act.
  • The word 'flight' has two different meanings: a plane journey, and the act of running away.
  • The law specifically forbids acts of this kind.
  • The George Cross is awarded to British civilians for acts of great bravery.
  • It was an act of extraordinary irresponsibility to leave someone who wasn't properly trained in charge of the machine.

act noun (PERFORMANCE)

C2 [ S ] behaviour that hides your real feelings or intentions:

Was she really upset or was that just an act?

[ C ] a person or group that performs a short piece in a show, or the piece that they perform:

Our next act is a very talented young musician.

B1 [ C ] a part of a play or opera:

Shakespeare's plays were written in five acts.
The hero does not enter until the second act/Act Two.

More examples

  • The main characters are offstage for most of the second act.
  • The best part of his stage act was a brilliant Elvis Presley impression.
  • I saw the worst comedy act I've ever seen last night - it was absolutely dreadful!
  • He put on an act of bravery, but I know that he was absolutely terrified.
  • They may seem to be very polite and friendly, but it's only an act.

act noun (LAW)

[ C ] specialized law a law or formal decision made by a parliament or other group of people who make the laws for their country:

an Act of Parliament
the Betting and Gaming Act
Almost two hundred suspects were detained in the UK last year under the Prevention of Terrorism Act.

(Definition of “act” from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)

“act” in American English

See all translations

actverb

us /ækt/

act verb (DO SOMETHING)

[ I ] to do something for a particular purpose or in a particular way:

She acted responsibly.
He acted as if he’d never seen me before.
She acted as (= performed in the position of) a tour guide for the group.
He said he was acting on (= doing something as a result of) the advice of his lawyer.

act verb (PERFORM)

[ I/T ] to perform in a movie, play, or television show:

[ T ] He acts the part of a small-town lawyer.
[ I ] She has acted in lots of television sitcoms.

Idiom(s)

Phrasal verb(s)

actnoun [ C ]

us /ækt/

act noun [ C ] (LAW)

law a law made by Congress or another legislature:

an act of Congress

act noun [ C ] (PERFORM)

one of a set of short performances that are parts of a show, or the person or group who performs one of these parts:

a circus act
fig. His story is just an act (= is pretended and not sincere).

An act is also one of the main parts of a play or opera:

The play is presented in three acts.

(Definition of “act” from the Cambridge Academic Content Dictionary © Cambridge University Press)

“act” in Business English

See all translations

actnoun

uk /ækt/ us

[ C ] something that someone does:

A partner may be held responsible for the acts of his co-partners committed in the name of the firm.
He has led an investigation into stock market manipulation and various illegal acts and swindles.
See also

[ C ] also Act LAW a law or formal decision made by a parliament or other group of elected law-makers:

The 2010 act, with its requirement for a review of financial controls, has helped drive up the cost of corporate audits by as much as 50%.
be a hard/tough act to follow informal

to be so good that it is unlikely that anyone or anything that comes after will be as good:

The company could lose momentum without its chief executive, who will be a hard act to follow.
get in on the act informal mainly UK US get into the act

to take advantage of or become involved with something that someone else started:

There's always a debate in the machine room about the product, long before the marketing men and editors get in on the act.
get your act together informal

to organize yourself so that you do things in an effective way:

Mr Dinsdale said it was crucial that the Department of Trade & Industry got its act together.

actverb [ I ]

uk /ækt/ us

to do something with the intention of achieving a particular result:

act to do sth Engineers will need to act quickly to repair the damaged pipes.
act quickly/swiftly/now Anyone who wants a fixed-rate deal should act now.
act decisively/improperly/responsibly It is now time for management to act decisively.
act against/in sb's interests There were claims that the management was acting against shareholders' interests.
Members should act in the best interests of the company.
act in good faith

to do something believing that it is the right thing to do:

Although errors of judgement were made, at all times the company's staff acted in good faith.

(Definition of “act” from the Cambridge Business English Dictionary © Cambridge University Press)