Bit of a fight (5)
I believe the answer is:
scrap
This clue is a double definition.
'bit' is the first definition.
(I know that bit can be written as scrap)
'a fight' is the second definition.
(a scrap is a minor fight)
'of' acts as a link.
(Other definitions for scrap that I've seen before include "Small (leftover) piece" , "boxing match?" , "A little bit of a fight" , "bundle" , "Informal fight for waste material" .)