Definition of act verb from the Oxford Advanced Learner's Dictionary

      

    act

     verb
    verb
    BrE BrE//ækt//
     
    ; NAmE NAmE//ækt//
     
    Verb Forms present simple I / you / we / they act
    BrE BrE//ækt//
     
    ; NAmE NAmE//ækt//
     
    he / she / it acts
    BrE BrE//ækts//
     
    ; NAmE NAmE//ækts//
     
    past simple acted
    BrE BrE//ˈæktɪd//
     
    ; NAmE NAmE//ˈæktɪd//
     
    past participle acted
    BrE BrE//ˈæktɪd//
     
    ; NAmE NAmE//ˈæktɪd//
     
    -ing form acting
    BrE BrE//ˈæktɪŋ//
     
    ; NAmE NAmE//ˈæktɪŋ//
     
    Making films, Producing a play
     
    jump to other results
    do something
  1. 1  [intransitive] to do something for a particular purpose or in order to deal with a situation It is vital that we act to stop the destruction of the rainforests. The girl's life was saved because the doctors acted so promptly. He claims he acted in self-defence.
  2. behave
  3. 2  [intransitive] to behave in a particular way + adv. John's been acting very strangely lately. act like somebody/something Stop acting like spoilt children! act as if/though… She was acting as if she'd seen a ghost. In spoken English people often use like instead of as if or as though in this meaning, especially in North American English:She was acting like she'd seen a ghost. This is not considered correct in written British English.
  4. pretend
  5. 3  [intransitive] to pretend by your behaviour to be a particular type of person + noun He's been acting the devoted husband all day. + adj. I decided to act dumb. He acts all macho, but he’s a real softie underneath.
  6. perform in play/movie
  7. 4  [intransitive, transitive] to perform a part in a play or film/movie Have you ever acted? Most of the cast act well. act something Who's acting (the part of) Hamlet? The play was well acted. See related entries: Making films, Producing a play
  8. perform function
  9. 5[intransitive] to perform a particular role or function act as something Can you act as interpreter? A five-year sentence should act as a deterrent to others. act like something hormones in the brain that act like natural painkillers
  10. have effect
  11. 6[intransitive] act (on something) to have an effect on something Alcohol acts quickly on the brain. It took a few minutes for the drug to act.
  12. Word Origin late Middle English: from Latin actus ‘event, thing done’, act- ‘done’, from the verb agere, reinforced by the French noun acte.Extra examples All citizens have a duty to act responsibly and show respect to others. George knew about the letter and acted accordingly. His defence was that he had acted in good faith. His lawyers are continuing to act for him. I suspected that he was acting out of malice. Jenny has been acting rather strangely recently. She is acting the role of Juliet. She was acting as if she owned the place. Stop acting like a spoiled child. The country’s highest court ruled that police had acted unlawfully. The government must act promptly to change this law. The government needs to act against the sale of these dangerous toys. The government was criticized for failing to act decisively. The jury accepted that he had acted in self defence. The play is well acted. We are all acting in the best interests of the children. A five-year sentence should act as a deterrent to others. He acts all macho but he’s a real softie underneath. He just can’t act. He’s been acting the devoted husband all day. I found myself acting the part of the happy newly-married wife. It is vital that we act to stop the destruction of the rainforests. John’s been acting very strangely lately. Most of these drugs acted directly on the blood vessels. Nuclear and non-nuclear matter act on each other. She was acting as if she’d seen a ghost. The bacteria act on sugars to form acids. The girl’s life was saved because the doctors acted so promptly. They acted at once/​immediately/​promptly/​quickly/​swiftly. We need to understand the forces that act on the spine. You acted very wisely in coming to me. to act wisely/​out of character/​fairly/​unlawfullyIdioms to behave in a stupid way in order to make people laugh, especially in a way that may also annoy them Quit playing the fool and get some work done! to behave in a way that is suitable for somebody of your age and not as though you were much younger Isn’t it time you started acting your age?
    behave/act as if you own the place, think you own the place
     
    jump to other results
    (disapproving) to behave in a very confident way that annoys other people, for example by telling them what to do
    Phrasal Verbsact for somebodyact on somethingact somethingoutact up
See the Oxford Advanced American Dictionary entry: act