Vibration from terrible snore can start to echo (9)
I believe the answer is:
resonance
'vibration' is the definition.
(resonance is a kind of vibration)
'terrible snore can start to echo' is the wordplay.
'terrible' indicates an anagram.
'start to' suggests taking the first letters.
The initial letter of 'echo' is 'e'.
'snore'+'can'='snorecan'
'snorecan' is an anagram of 'resonanc'.
'resonanc'+'e'='RESONANCE'
'from' is the link.
(Other definitions for resonance that I've seen before include "Vibrancy" , "Sound amplification" , "Sonority" , "Sympathetic vibration" , "Deep, clear, ringing quality" .)