act (acts plural & 3rd person present) (acting present participle) (acted past tense & past participle )
1 verb When you act, you do something for a particular purpose.
The deaths occurred when police acted to stop widespread looting and vandalism... V
I do not doubt that the bank acted properly. V adv/prep
2 verb If you act on advice or information, you do what has been advised or suggested.
A patient will usually listen to the doctor's advice and act on it. V on/upon n
3 verb If someone acts in a particular way, they behave in that way.
(=behave)
...a gang of youths who were acting suspiciously... V adv
He acted as if he hadn't heard any of it... V as if
Open wounds act like a magnet to flies. V like n
4 verb If someone or something acts as a particular thing, they have that role or function.
He acted both as the ship's surgeon and as chaplain for the men. V as/like n
5 verb If someone acts in a particular way, they pretend to be something that they are not.
Chris acted astonished as he examined the note... V adj
Kenworthy had tried not to act the policeman. V n
6 verb When professionals such as lawyers act for you, or act on your behalf, they are employed by you to deal with a particular matter.
...the law firm that acted for Diana during her marriage split... V for n
Because we travelled so much, Sam and I asked a broker to act on our behalf. V prep
7 verb If a force or substance acts on someone or something, it has a certain effect on them.
He's taking a dangerous drug: it acts very fast on the central nervous system... V on/upon n
8 verb If you act, or act a part in a play or film, you have a part in it.
She confessed to her parents her desire to act... V
She acted in her first film when she was 13 years old. V in n
9 n-count An act is a single thing that someone does.
FORMAL oft N of n
Language interpretation is the whole point of the act of reading...
10 n-sing If you say that someone's behaviour is an act, you mean that it does not express their real feelings.
(=pretence)
His anger was real. It wasn't an act.
11 n-count An Act is a law passed by the government.
...an Act of Parliament.
12 n-count An act in a play, opera, or ballet is one of the main parts into which it is divided.
oft N num
Act II contained one of the funniest scenes I have ever witnessed...
13 n-count An act in a show is a short performance which is one of several in the show.
This year numerous bands are playing, as well as comedy acts...
14 If you catch someone in the act, you discover them doing something wrong or committing a crime.
catch sb in the act phrase V inflects
The men were caught in the act of digging up buried explosives.
15 If someone who has been behaving badly cleans up their act, they start to behave in a more acceptable or responsible way.
INFORMAL
clean up one's act phrase V inflects
The nation's advertisers need to clean up their act.
16 If you get in on the act, you take part in or take advantage of something that was started by someone else.
INFORMAL
get in on the act phrase V inflects
In the 1970s Kodak, anxious to get in on the act, launched its own instant camera.
17 You say that someone was in the act of doing something to indicate what they were doing when they were seen or interrupted.
in the act of phrase v-link PHR -ing
Ken was in the act of paying his bill when Neil came up behind him.
18 If you get your act together, you organize your life or your affairs so that you are able to achieve what you want or to deal with something effectively.
INFORMAL
get one's act together phrase V inflects
The Government should get its act together...
19
→
to act one's age
→
age
→
to act the fool
→
fool act out phrasal verb If you act out an event which has happened, you copy the actions which took place and make them into a play.
I used to come home and act out the movie for the kids. V P n (not pron), Also V n P act up
1 phrasal verb If something is acting up, it is not working properly.
INFORMAL usu cont
(=play up)
She was messing with the coffee pot, which was acting up again. V P
2 phrasal verb If a child is acting up, they are behaving badly.
INFORMAL usu cont
(=play up)
