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Definition of
act up phrasal verb
from the Oxford Advanced Learner's Dictionary
act up
phrasal verb
jump to other results
act up
(informal)
to behave badly
The kids started acting up.
to not work as it should
How long has your ankle been acting up?
See
act up
in the Oxford Advanced American Dictionary
Other results
All matches
clean up your act
Idioms
clean up your act
Nearby words
actuary
noun
actuate
verb
act up
phrasal verb
act upon
phrasal verb
acuity
noun
previously
adverb
From the
Word list
Oxford 3000
B1
Oxford Learner's Dictionaries Word of the Day