Mock son's company very loudly (5)

I believe the answer is:

scoff

'mock' is the definition.
(thesaurus)

'son's company very loudly' is the wordplay.
'company' becomes 'co' (abbreviation).
'very loudly' becomes 'ff'.
's'+'co'+'ff'='SCOFF'

(Other definitions for scoff that I've seen before include "Jeer; eat greedily" , "Greedily consume" , "Quickly swallow" , "Speak scornfully; eat" , "Furiously swallow" .)

I've seen this clue in The Independent.

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