acted up; acting up; acts up
Definition of act up
(Entry 1 of 2)
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
\ ˈakt-ˈəp
\
\
Definition of ACT UP (Entry 2 of 2)
AIDS Coalition to Unleash Power
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“Act up.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/act%20up. Accessed 25 Jun. 2022.
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Time Traveler for act up
The first known use of act up was in 1879
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