vệ sinh 衛生 "hygiene"
Mandarin wèishēng; Cantonese wai6 sang1
I don't know why the people downvote this comments about Chinese, but I find them quite interesting, please keep posting the ethymology.
(I thought it came from French "vesin", but apparently I made up that word and it doesn't exist)
It only took me 2 years of Duolingo to learn how to say bathroom in vietnamese. Why is this not in an earlier lesson?