Incorrect cab MOT causes fighting (6)
I believe the answer is:
combat
'fighting' is the definition.
(I know that fighting can be written as combat)
'incorrect cab mot' is the wordplay.
'incorrect' is an anagram indicator.
'cab'+'mot'='cabmot'
'cabmot' is an anagram of 'COMBAT'.
'causes' acts as a link.
(Other definitions for combat that I've seen before include "Fight against; fighting" , "Oppose" , "Military action" , "type of jacket" , "Take action to deal with - fight" .)