Consort very disturbed by argument (11)
I believe the answer is:
controversy
'argument' is the definition.
(I know that argument can be written as controversy)
'consort very disturbed' is the wordplay.
'disturbed' is an anagram indicator (the order of letters is disturbed).
'consort'+'very'='consortvery'
'consortvery' with letters rearranged gives 'CONTROVERSY'.
'by' is the link.
(Other definitions for controversy that I've seen before include "Long heated debate" , "Prolonged public dispute" , "Heated dispute" , "Debate (whose pronunciation causes debate!)" , "Polemics" .)