Duck to baste -- around medium (4)

I believe the answer is:

smew

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'duck' is the definition.
(smew is a kind of duck)

'baste around medium' is the wordplay.
'around' indicates the central letters.
'medium' becomes 'mew' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
The middle letter of 'baste' is 's'.
's'+'mew'='SMEW'

'to' acts as a link.

Can you help me to learn more?

(Other definitions for smew that I've seen before include "Sea duck" , "Diver" , "Species of merganser" , "Small merganser" , "Bird" .)

I've seen this clue in The Telegraph.

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