A bit of an upset farm gent (8)
I believe the answer is:
fragment
'a bit' is the definition.
(I've seen this before)
'an upset farm gent' is the wordplay.
'an upset' is an anagram indicator.
'farm'+'gent'='farmgent'
'farmgent' with letters rearranged gives 'FRAGMENT'.
'of' acts as a link.
(Other definitions for fragment that I've seen before include "Particle" , "Broken-off piece" , "Piece broken off something else" , "Shard" , "Small piece" .)