Don's conjecture (6)
I believe the answer is:
assume
I believe this is a double definition.
'don's' is the first definition.
(thesaurus)
'conjecture' is the second definition.
(thesaurus)
(Other definitions for assume that I've seen before include "Take for granted, suppose" , "Take for granted or agreed" , "Wrongly take" , "Take for granted or take upon oneself" , "Take (control)" .)