Grail seeker (7)
I believe the answer is:
galahad
'grail seeker' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for galahad that I've seen before include "K" , "One of Arthur's knights" , "The most virtuous knight at the Arthurian Round Table" , "the noblest of men" , "Chivalrous knight" .)