0 If a person, especially a child, acts up, they behave badly:
Her shoulder was acting up (= hurting because of injury).
My car always acts up in cold weather.
Sophie got bored and started acting up.
1 to behave badly:
The little girl was acting up, so her mother took her out of the restaurant.
2 to operate badly:
My car is acting up again - I don't know what's wrong with it.
3 to become active:
Her allergies acted up when she went hiking in the woods.
NEW WORDS
European
May 10, 2021
WORD OF THE DAY
Shimmer
act up