Sound heard in a canyon (4)
I believe the answer is:
echo
'sound heard in a canyon' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for echo that I've seen before include "next to delta" , "Nymph; E (radio comms.)" , "Mimic" , "Greek nymph, spurned by Narcissus, who pined away until only her voice remained" , "one catches on the rebound?" .)