- act
- 1
noun (C)
1 ACTION (C) a particular kind of action: a criminal act | act of kindness/revenge/courage etc: The Bishop condemned the attack as an act of mindless violence. | a supreme act of heroism | the sexual act (=the act of having sex)2 be in the act of doing sth to be doing something at a particular moment, especially something that you should not do: catch sb in the act (of doing sth): The photo shows her in the act of raising her gun to fire. | The thief was caught in the act.3 LAW (C) a law that has been officially accepted by Parliament or Congress: the 1991 Prevention of Terrorism Act | an act of Congress4 PRETENDING (singular) insincere behaviour in which you pretend to have a particular kind of feeling: A lot of people think Betty's very kind and caring, but it's all just a big act. | put on an act (=pretend to have a particular feeling): He isn't really ill - he's just putting on an act.5 get your act together informal to do something in a more organized way or use your abilities more effectively: She could be an excellent photographer, if only she got her act together a bit more.6 get in on the act informal to take part in an activity that someone else has started, especially in order to get a share of the advantages for yourself.7 PLAY (C) one of the main parts into which a stage play, opera etc is divided: Hamlet eventually kills the king in Act 5. | Everything is resolved in the final act.8 PERFORMANCE (C) one of the several short performances in a theatre or circus (1) show: They used to do a comedy act together.9 PERFORMER (C) a performer, singer, group of musicians etc: top-selling British act `The Happy Mondays'10 act of God an event that is caused by natural forces, such as a storm, flood, or fire, which you cannot prevent or control11 act of worship an occasion when people pray together and show their respect for God12 balancing/juggling act the action of doing several different kinds of work at the same time-see also: clean up your act clean 2 2 verb1 DO SOMETHINGa) (I) to do something to deal with an urgent problem, especially by using your official power or authority: The UN Security Council must act to end the war in Bosnia.b) (intransitive always + adv/prep) to do something in a particular way or for a particular reason: The killer claims he was acting in self-defence. | I acted more out of compassion than anything else. | act in good faith (=do something honestly without intending to deceive anyone): The shop manager says they acted in good faith and that they didn't know the camera was damaged. | act on (sb's) advice/orders/suggestion etc (=do what someone has advised, ordered etc): Acting on a friend's advice, he bought $50,000 of shares in a television company. | act on information (=do something because of information you have received): The police were acting on information from a member of the public.2 BEHAVE (intransitive always + adv/prep) to behave in a particular way: act strangely/stupidly/correctly etc: Henry's been acting very strangely recently. | The teacher acted perfectly correctly under the circumstances. | act like/act as if: If you act like a child, you're going to be treated like a child. | He acted as if he'd never seen me before. | act your age spoken (=used to tell someone to be sensible and stop behaving like a child) | act the fool (=behave in a stupid and annoying way): Stop acting the fool, will you!3 HAVE AN EFFECTa) to have a particular effect or use(+ as): The sugar in the fruit acts as a preservative. (+ on): Antibiotics act on the bacteria that cause the disease.b) to start to have an effect: It takes a couple of minutes for the drug to act.4 PRETEND (I, T) to pretend to have particular feelings, qualities etc: act innocent/stupid/hurt etc: She suddenly started acting all upset so that the others would feel sorry for her. | act the fool/hero etc: Whenever they're in public he always acts the loving husband. | act as if/act like: They were all trying to act as if nothing had happened.5 PLAY/FILM ETC (I, T) to perform in a play or film: I first started acting when I was 12 years old. | act a part/role etc: Who acted the part of Miss Ceeley? | well/badly acted (=performed well or badly): I thought the play was extremely well acted.6 LAWYER ETC act for sb/act on sb's behalf to represent someone, especially in a court of law or by doing business for them: I'm acting on behalf of my client, Mr Harding.7 DO THE JOB OF act as to do a particular job for a short time, for example while the usual person is absent: Mrs Odell is on holiday, and I'm acting as her replacement till she gets back. | My brother speaks French - he will act as interpreter.-see also: acting 1 act sth out phrasal verb (T)1 if a group of people act out an event, they show how it happened by pretending to be the people who were involved in it2 to express your feelings about something through your behaviour or actions, especially when you have been feeling angry or nervous: Teenagers can act out their anxieties in various aggressive ways.act up phrasal verb (I) informal1 if children act up, they behave badly2 if a machine or part of your body acts up, it does not work properly: The photocopier has started acting up again.
Longman dictionary of contemporary English. 2004.