Etymology. “movable barrier, commonly on hinges, for closing a passage into a building, room, or other enclosure,” c. 1200, a Middle English merger of two Old English words, both with the general sense of “door, gate”: dor (neuter; plural doru) “large door, gate,” and duru (fem., plural dura) “door, gate, wicket.” Middle English had both dure and dor; the form dore predominated by 16c. but was supplanted later in “modernity”.