I’d turned back, seeing difference of opinion (8)
I believe the answer is:
division
'difference of opinion' is the definition.
(I've seen this before)
'i'd turned back seeing' is the wordplay.
'turned back' says the letters should be written in reverse.
'seeing' becomes 'vision'.
'id' written backwards gives 'di'.
'di'+'vision'='DIVISION'
(Other definitions for division that I've seen before include "It can be long or short, in arithmetic" , "Difference of opinion" , "military unit" , "A number of teams grouped together in sport according to ability" , "Large army unit" .)