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c.1300, probably from Latin latrina, contraction of lavatrina "washbasin, washroom," from lavatus, past participle of lavare "to wash" (see lave) + -trina, suffix denoting "workplace." Its reappearance in 1640s is probably a re-borrowing from French; especially of a privy of a camp, barracks, college, hospital, etc. Latrine rumor "baseless gossip" (of the kind that spreads in conversations in latrines) is military slang, first recorded 1918.