Mythical hybrid (7)
I believe the answer is:
centaur
'mythical hybrid' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for centaur that I've seen before include "Mythical beast, half horse and half man" , "Mythical equine creature" , "Mythical semi-equine beast" , "Greek mythical creature" , "Mythical hybrid" .)