Red wine's having great effect, knocking out petty officer (4)

I believe the answer is:

tent

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'red wine's' is the definition.
(type of Spanish wine)

I cannot understand how the remainder of the clue works.

(Other definitions for tent that I've seen before include "Camping accommodation" , "pavilon" , "Marquee" , "Cloth shelter" , "Portable shelter for camper" .)

I've seen this clue in The Times.

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