At a court rogue in charge is overbearing (10)
I believe the answer is:
autocratic
'is overbearing' is the definition.
(thesaurus)
'at a court rogue in charge' is the wordplay.
'rogue' indicates anagramming the letters (letters go rogue).
'in charge' becomes 'ic' (abbreviation for 'in charge').
'at'+'a'+'court'='atacourt'
'atacourt' is an anagram of 'autocrat'.
'autocrat'+'ic'='AUTOCRATIC'
(Other definitions for autocratic that I've seen before include "Unrestrainedly powerful" , "Having absolute power" , "bossy" , "Totalitarian" .)