Origins
The English word "armoire" was borrowed from French, where it means a wardrobe or large cupboard. The French term descends from Old French "armaire" or "almarie," which came from Latin "armārium" — a closet or chest specifically for storing "arma" (tools, implements, or weapons).
The semantic evolution is a journey from the battlefield to the bedroom. A Roman armārium held weapons and tools. Through the medieval period, as furniture design evolved, these large storage pieces gradually transitioned from martial to domestic use. By the time English borrowed "armoire" from French, it primarily denoted a clothes-storage cabinet.
Proto-Indo-European Roots
Latin "arma" traces to Proto-Indo-European *h₂er- (to fit together), a root of remarkable reach. It produced "arm" (body part and weapons), "army," "armor," "armada," and even "art" — through Latin "ars," which originally described the skill of fitting things together. The English word "aumbry," a recessed church cupboard, is a doublet of "armoire" that arrived through a different Old French pathway.