Minor row (4)
I believe the answer is:
spat
'minor row' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for spat that I've seen before include "Ejected saliva from the mouth" , "Unimportant quarrel between Pats" , "Showed contempt" , "Trivial quarrel" , "Minor conflict" .)