act up

verb
acted up; acting up; acts up

Definition of act up

 (Entry 1 of 2)

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
b : show off
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

ACT UP

abbreviation

Definition of ACT UP (Entry 2 of 2)

AIDS Coalition to Unleash Power

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Synonyms for act up

Synonyms: Verb

act out, carry on, misbehave

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Examples of act up in a Sentence

Verb

the two-year-old was acting up in church so much that her dad had to take her outside you should have seen the boys acting up when they put on their aprons

First Known Use of act up

Verb

1879, in the meaning defined at sense 1

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Dictionary Entries near act up

actuary

actuate

actuator

act up

ACT UP

actus

acu-

Statistics for act up

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Time Traveler for act up

The first known use of act up was in 1879

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Thesaurus: All synonyms and antonyms for act up

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