Wordnet 3.0
VERB (2)
1.
misbehave badly;
act in a silly or improper way;
- Example: "The children acted up when they were not bored"[syn: act up, carry on]
2. make itself felt as a recurring pain;
- Example: "My arthritis is acting up again"
WordNet (r) 3.0 (2006):
act up
v 1: misbehave badly; act in a silly or improper way; "The
children acted up when they were not bored" [syn: act up,
carry on]
2: make itself felt as a recurring pain; "My arthritis is acting
up again"