Mythical youth (6)
I believe the answer is:
adonis
'mythical youth' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for adonis that I've seen before include "striking youth" , "Beautiful (Greek) man" , "Legendary lover" , "In Greek myth, handsome youth beloved of Aphrodite" , "Aphrodite's beloved" .)