Stuffy complaint (7)

I believe the answer is:

catarrh

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'complaint' is the definition.
(medical complaint)

I cannot understand how the rest of the clue works.

(Other definitions for catarrh that I've seen before include "(Inflammation causing) excessive mucus" , "Inflammation often blocking the nose" , "Inflammation of mucous membrane with watery discharge" , "Problem with cold" , "Arch rat with inflamed mucous membrane" .)

I've seen this clue in The Globe and Mail and The Telegraph.

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