A man’s son making disapproving sound (4)

I believe the answer is:

hiss

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'disapproving sound' is the definition.
(I've seen this before)

'a man's son' is the wordplay.
'a man' becomes 'his' (I can't explain this - if you can you should believe this answer much more).
'son' becomes 's'.
'his'+'s'='HISS'

'making' is the link.

Can you help me to learn more?

(Other definitions for hiss that I've seen before include "Sound of serpent" , "showing contempt?" , "Show disapproval" , "Make disapproving sound" , "less welcome sign?" .)

I've seen this clue in The Times.

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