Cancel fight (5)
I believe the answer is:
scrap
I believe this clue is a double definition.
'cancel' is the first definition.
(I've seen this in another clue)
'fight' is the second definition.
(a scrap is a minor fight)
(Other definitions for scrap that I've seen before include "Ditch - fight" , "bundle" , "Dispose of" , "Turn into refuse" , "Tiny piece; abolish" .)