Deliver somewhat discontented ruminant (4)

I believe the answer is:

deer

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'ruminant' is the definition.
(I know that deer is a type of ruminant)

I can't explain the remainder of the clue.

(Other definitions for deer that I've seen before include "Red, roe or fallow" , "Sledge animals for Father Christmas" , "Wild animal" , "The male is a stag" , "Hoofed grazing animal" .)

I've seen this clue in The Irish Times.

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