A revolutionary's hurt (4)
I believe the answer is:
ache
'hurt' is the definition.
(synonyms)
'a revolutionary's' is the wordplay.
'revolutionary' becomes 'che' (Che Guevara the Marxist revolutionary).
'a'+'che'='ACHE'
(Other definitions for ache that I've seen before include "suffering" , "agony" , "Feel sore" , "painful" , "Dull steady pain" .)