Hedonist's opposite (7)
I believe the answer is:
ascetic
'hedonist's opposite' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for ascetic that I've seen before include "One practising self-denial as a discipline" , "Practising severe self-discipline" , "Person who leads a severely simple life" , "Abstemious, self-denying" , "Severe self-disciplinarian" .)