狐臭

狐臭 is a sensitive topic in China — culturally, East Asian populations have far lower rates of the gene that causes strong underarm odor (ABCC11), so having 狐臭 is more socially conspicuous than in the West. Ads for treatment products are common; the term itself is medical-neutral, but pointing it out about someone is rude.

Literally 'fox stink' — 狐 'fox' + 臭 'stinky'. Foxes have a strong musky scent from their anal glands, so traditional Chinese named human underarm odor by analogy. The medical synonym 腋臭 (yèchòu, 'armpit-stink') is more clinical.