Mum turning around to go (4)
I believe the answer is:
shot
'go' is the definition.
(I've seen this before)
'mum turning around to' is the wordplay.
'mum' becomes 'sh' (both can mean to be quiet).
'turning around' is a reversal indicator.
'to' written backwards gives 'ot'.
'sh'+'ot'='SHOT'
(Other definitions for shot that I've seen before include "Darted" , "glass of spirits" , "Fired - attempt" , "Sent a bullet" , "Try -- ammunition" .)