Unquestioning follower (8)
I believe the answer is:
myrmidon
'unquestioning follower' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for myrmidon that I've seen before include "Faithful follower, after the Greek soldiers loyal to Achilles" , "A warrior following Achilles to Troy - my Nimrod (anag)" , "I'll do as the captain says" , "Henchman" , "keen backer-up" .)