Spot feathers in sink (4,4)

I believe the answer is:

drop down

'sink' is the definition.
(synonyms)

'spot feathers' is the wordplay.
'spot' becomes 'drop' (drop is a kind of spot).
'feathers' becomes 'down' (down can mean bird feathers).
'drop'+'down'='DROP DOWN'

'in' is the link.

I've seen this clue in The Telegraph.

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