Her wit could make you move in agony (6)
I believe the answer is:
writhe
'move in agony' is the definition.
'writhe' can be an answer for 'move' (writhing is a kind of moving). I'm not sure about the 'in agony' bit.
'her wit could make you' is the wordplay.
'could make you' indicates anagramming the letters.
'her'+'wit'='herwit'
'herwit' with letters rearranged gives 'WRITHE'.
Can you help me to learn more?
(Other definitions for writhe that I've seen before include "Struggle" , "worm" , "Thrash" , "Twist as in pain" , "6, maybe in agony" .)