Insult someone male, equally hollow (4,1,5)

I believe the answer is:

cock a snook

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'insult someone' is the definition.
I know nothing about this answer so I cannot judge whether this works.

'male equally hollow' is the wordplay.
'male' becomes 'cock' (male chicken).
'equally' becomes 'as' (synonyms).
'hollow' becomes 'nook' (I can't justify this - if you can you should give a lot more credence to this answer).
'cock'+'as'+'nook'='COCK A SNOOK'

Can you help me to learn more?

(Other definitions for cock a snook that I've seen before include "Show contempt (with thumb touching nose and fingers spread)" , "Gesture contemptuously" .)

I've seen this clue in The Times.

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