Trace ring (4)
I believe the answer is:
echo
I believe this is a double definition.
'trace' is the first definition.
(thesaurus)
'ring' is the second definition.
('echo' can be a synonym of 'ring')
(Other definitions for echo that I've seen before include "Reiterate" , "from Brussels?" , "Be suggestive of" , "one catches on the rebound?" , "A natural sound reflection" .)