A French blonde is not just (6)

I believe the answer is:

unfair

'is not just' is the definition.
('unfair' is the opposite to 'just')

'a french blonde' is the wordplay.
'a french' becomes 'un' ('a' in French).
'blonde' becomes 'fair' (similar in meaning).
'un'+'fair'='UNFAIR'

(Other definitions for unfair that I've seen before include "Not equitable or even-handed" , "not right" , "Wrongful - discriminatory" , "Not equitable or blond" , "Swizz!" .)

I've seen this clue in The Daily Express.

Want a hint initially instead of a full solution? Install my app