Behave testily? (3)
I believe the answer is:
try
'behave' is the definition.
The definition and answer can be both related to bodily activities as well as being verbs in their base form.
Maybe you can see an association between them that I don't see?
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for try that I've seen before include "Gorse" , "A rugby score, result of effort" , "Four rugby points" , "crack" , "Make an attempt" .)