Slaughter - or trim the feathers! (3,4)

I believe the answer is:

mow down

'slaughter' is the definition.
(synonyms)

'trim the feathers' is the wordplay.
'trim' becomes 'mow' (I've seen this in another clue).
'the feathers' becomes 'down' (down can mean bird feathers).
'mow'+'down'='MOW DOWN'

'or' acts as a link.

I've seen this clue in the Sydney Morning Herald.

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