On bad terms (2,4)
I believe the answer is:
at odds
'on bad terms' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for at odds that I've seen before include "At variance (with)" , "Conflicting (with)" , "In conflict with, oppposed to (2,4)" , "Not in agreement" , "Opposed, in conflict with" .)