Stop hands in conversation (5)
I believe the answer is:
pause
'stop' is the definition.
(I know that pause is a more specific form of break up)
'hands in conversation' is the wordplay.
'hands' becomes 'paws' ('paw' can be a synonym of 'hand').
'in conversation' shows a homophone (sound like).
'paws' sounds like 'PAUSE'.
(Other definitions for pause that I've seen before include "Hesitate; delay" , "Temporary cessation" , "Intermission" , "Wait" , "Stoppage" .)