Unquestioning (8)
I believe the answer is:
implicit
'unquestioning' is the definition.
(I know that unquestioning can be written as implicit)
This is the entire clue.
(Other definitions for implicit that I've seen before include "Indirectly implied" , "Understood but not openly stated" , "I clip Tim (anag.)" , "Not in so many words" , "Inferred" .)