Minor spat (4)
I believe the answer is:
tiff
'minor spat' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for tiff that I've seen before include "A minor quarrel of disagreement" , "A petty quarrel or difference" , "Quarrel (colloq.)" , "pet" , "A small quarrel or spat" .)