"Hello! . . . lo! . . . lo" effect (4)
I believe the answer is:
echo
(Other definitions for echo that I've seen before include "Reverberate - nymph spurned by Narcissus" , "Let's hear it again for the Greek nymph who loved Narcissus in vain" , "Trace call" , "from Brussels?" , "Greek girl in love with Narcissus" .)