Owing to student conflict (4)
I believe the answer is:
duel
'conflict' is the definition.
(I know that duel is a type of combat)
'owing to student' is the wordplay.
'owing' becomes 'due' (similar in meaning).
'to' means one lot of letters go next to another.
'student' becomes 'l' (as in L-plates for learner drivers).
'due'+'l'='DUEL'
(Other definitions for duel that I've seen before include "Fight over a point of honour" , "Single combat" , "Fight between two persons" , "Contest between two with deadly weapons" , "Gentlemen's disagreement" .)