By sound of it, put up with a swine (4)

I believe the answer is:

boar

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'a swine' is the definition.
(male pig)

I cannot understand how the rest of the clue works.

(Other definitions for boar that I've seen before include "Male swine" , "The head for drink Falstaff had" , "Uncastrated male hog" , "A wild male pig" , "Sow's mate" .)

I've seen this clue in The Everyman puzzle in The Observer.

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