late 14c., "room where wearing apparel is kept," earlier "a private chamber" (c.1300), from O.N.Fr. warderobe, variant of O.Fr. garderobe "place where garments are kept," from warder "to keep, guard" (see ward (v.)) + robe "garment" (see robe). Meaning
"a person's stock of clothes for wearing" is recorded from c.1400. Sense of "movable closed cupboard for wearing apparel" is recorded from 1794. Meaning "room in which theatrical costumes are kept" is attested from 1711.