Folding door

[f. FOLDING ppl. a. + DOOR.] A door consisting of two parts hung on opposite jambs, so that their edges come into contact when the door is closed. Now usually pl. in same sense.

  In the mod. sense of the adj. the name is more appropriate when, as is often the case, each of the parts of the door consists of two or more leaves, hinged so as to fold up when the door is open. ‘Folding doors’ are often used to form a removable partition between two adjacent rooms; hence the term is sometimes loosely applied to a partition used for the same purpose, but opened by lateral sliding of its parts.

1611.  Cotgr., s.v. Batant, A foulding, or two leaued doore.

1723.  Chambers, trans. Le Clerc’s Treat. Archit., I. 102. In one of the Folding Doors is usually a Wicket, or little Gate, through which People on foot ordinarily pass.

1794.  Mrs. Radcliffe, Myst. Udolpho, xix. Through a folding-door she passed from the great hall to the ramparts.

1829.  University Instr., in Willis & Clark, Cambridge (1886), III. 103. The four Schools … are to be so constructed as to communicate with each other, when required, by large double folding doors.

1838.  Lytton, Calderon, i. The folding-doors were thrown open, and all conversation ceased at the entrance of Don Roderigo Calderon.

1882.  Ouida, Maremma, I. 125. In the wall of this entrance-chamber was a stone door, a double or, as it is commonly termed, folding door, tight closed.

  So Folding gates.

1824.  Scott, Redgauntlet, Let. xi. They rode into the outer courtyard, through the muckle faulding yetts, and aneath the auld portcullis.

1870.  Bryant, Iliad, I. XII. 396.