A court edict (3)
I believe the answer is:
act
'edict' is the definition.
(thesaurus)
'a court' is the wordplay.
'court' becomes 'ct'.
'a'+'ct'='ACT'
(Other definitions for act that I've seen before include "Major division of play" , "Perform theatrically" , "Assumed attitude" , "Take part in a play" , "performing group" .)