Creator of Mickey Mouse (6)
I believe the answer is:
disney
'creator of mickey mouse' is the definition.
(I know that Mickey Mouse creator Disney)
This is all the clue.
(Other definitions for disney that I've seen before include "Creator of Donald Duck" , "Walt - - , animator" , "Walt the film-maker" , "Walt . . . . . ., film maker (6)" , "US cartoon pioneer" .)