Couple of body parts in horse? (8)

I believe the answer is:

chestnut

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'horse?' is the definition.
(I know that chestnut is a type of horse)

I don't understand the remainder of the clue.

(Other definitions for chestnut that I've seen before include "comedian's overused line?" , "Wood" , "not a cracker!" , "Brown horse" , "Horse coat colour" .)

I've seen this clue in The Times.

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