Echo, reverberate (7)
I believe the answer is:
resound
This clue is a double definition.
'echo' is the first definition.
(I know that echo can be written as resound)
'reverberate' is the second definition.
(I know that reverberate can be written as resound)
(Other definitions for resound that I've seen before include "Echo" , "ring" , "Reverberate" .)