Not exactly unfair? (6)
I believe the answer is:
unjust
'unfair?' is the definition.
(I know that unfair can be written as unjust)
'not exactly' is the wordplay.
'not' becomes 'un' (prefix meaning 'not').
'exactly' becomes 'just' (synonyms).
'un'+'just'='UNJUST'
(Other definitions for unjust that I've seen before include "Unfair" , "Not fair or equitable" , "Biased" , "Partisan - not fair" , "Inequitable" .)