Turn back, breaking rank as superior (8)
I believe the answer is:
arrogant
'superior' is the definition.
(I've seen this before)
'turn back breaking rank as' is the wordplay.
'turn' becomes 'go' (a person's move in a board game).
'back' says the letters should be written backwards.
'breaking' is an insertion indicator.
'rank as' becomes 'arrant' (synonyms. I am not sure about the 'as' bit.).
'go' backwards is 'og'.
'og' placed into 'arrant' is 'ARROGANT'.
Can you help me to learn more?
(Other definitions for arrogant that I've seen before include "Getting backs up" , "Haughty - imperious" , "Overly self-important" , "Showing an offensive sense of superiority" , "Overweening" .)