Hairstyle for a revolutionary (4)
I believe the answer is:
afro
'hairstyle' is the definition.
(afro is a kind of hairstyle)
'for a revolutionary' is the wordplay.
'revolutionary' is an anagram indicator.
'for'+'a'='fora'
'fora' anagrammed gives 'AFRO'.
(Other definitions for afro that I've seen before include "One cut" , "shock treatment?" , "Bushy hairstyle" , "Type of hairstyle - from Africa" , "Luxuriant (black) hairstyle" .)