act up

verb

Definition of act up

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

First Known Use of act up

1879


ACT UP

abbreviation

Definition of ACT UP

AIDS Coalition to Unleash Power


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