Noted race loser (4)
I believe the answer is:
hare
'noted race loser' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for hare that I've seen before include "Run with great speed" , "Fast runner" , "Mammal like a large rabbit" , "As mad as this March animal" , "Game, -- and hounds" .)