Degrading form of feuding overwhelming one in Scotland (10)
I believe the answer is:
unedifying
'degrading' is the definition.
(I've seen this before)
'form of feuding overwhelming one in scotland' is the wordplay.
'form of' indicates anagramming the letters (the letters need to be in another 'form').
'overwhelming' is an insertion indicator.
'one in scotland' becomes 'yin' (Scottish dialect term for 'one').
'feuding' with letters rearranged gives 'unedifg'.
'unedifg' enclosing 'yin' is 'UNEDIFYING'.
(Another definition for unedifying that I've seen is " degrading".)