Gossip starts to jar as well (3)
I believe the answer is:
jaw
'gossip' is the definition.
(synonyms)
'starts to jar as well' is the wordplay.
'starts to' says to take the initial letters.
The initial letters of 'jar as well' is 'JAW'.
(Other definitions for jaw that I've seen before include "Part of the head" , "Chin bone" , "Facial bone" , "It frames the mouth and holds the teeth" , "Talk incessantly" .)