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act up

verb

Definition of act up

  1. intransitive verb
  2. 1 :  to act in a way different from that which is normal or expected: as a :  to behave in an unruly, recalcitrant, or capricious manner <the children were acting up> b :  show off c :  to function improperly <this typewriter is acting up again>

  3. 2 :  to become active or acute after being quiescent <her rheumatism started to act up>



Examples of act up in a sentence

  1. <the two-year-old was acting up in church so much that her dad had to take her outside>

  2. <you should have seen the boys acting up when they put on their aprons>



1903

First Known Use of act up

1903


ACT UP

abbreviation

Definition of ACT UP

  1. AIDS Coalition to Unleash Power




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