A corner-stone of a wall or building; also, one of the wedge-shaped stones of an arch. Now usually quoin, n.; cf. coign, n. 2. Hence coin-stone n. Obs…

Architecture and Building. In an open timber roof: a supporting post attached to the hammerbeam or the principal rafter; a pendant-post; a spandrel…

One of the stones which form part of an arch or a vault, usually having the sides slightly inclined towards each other.

Architecture. The point from which an arch or vault rises; the support or impost at each end of an arch. Cf. later spring, n.1 9a, spring, v.1 17b.

The triangular space between the outer curve of an arch and the rectangle formed by the mouldings enclosing it, frequently filled in with ornamental…

Architecture. The point at which an arch or vault rises from a support or impost (impost, n.2 1); the commencement of curvature in an arch. Also…

The height of a roof (esp. an arched roof) or ceiling above the floor; (also) the height of the vertex of an arch above the springing line. Now…

Architecture. The return of the dripstone at the spring of an arch: cf. knee, n. 10. Obsolete.

plural. The voussoirs of an arch. Obsolete. rare.

The principal side, often vertical or steeply sloping, presented by an object; the ‘front’, as opposed… Architecture. The side of a structure, etc…

Architecture. Degree of pointedness. Only in of the third (also fourth) point. Obsolete.

Architecture. The curved side of an arch, between the keystone and the foot; the haunch or flank. Obsolete.

The continuously curved part of an arch.

Architecture. The arc of smaller radius at the springing of an elliptical or many-centred arch. Now usually viewed as the ‘haunch’ of the arch, and…

Architecture. The springing-line of an arch; the sloping surface on which either extremity of an arch rests; a course of stone or brickwork, an…

In various applications indicating the direction, angle, etc., of the elements forming an arch, or the manner of construction of an arch; spec.…

Architecture. The point at which an arch or vault rises from a support or impost (impost, n.2 1); the commencement of curvature in an arch. Cf…

Architecture. = tympanum, n. 3.

Architecture and Building. The space formed between one side of the outer curve of an arch, a wall, and the ceiling or framework; a spandrel. Obsolete…

Architecture. The curved walls and material filling the space behind these which form and sustain an arch in a vault. Cf. haunch, n.1 3a.

Architecture, Building, and Engineering. The haunch or flank of an arch. Obsolete. rare.

= tierce, n.1 point: see quot.

Building. The keystone, or any one of the wedge-shaped stones, of an arch; = voussoir, n. Obsolete. rare.

The under curve or inner contour of an arch, from impost to impost; the band of mouldings which ornaments this curve.

The width of an arch between its pillars. Obsolete. rare.

The under horizontal face of an architrave or overhanging cornice; the under surface of a lintel, vault, or arch; a ceiling.

Each of the two stones adjacent to the keystone of an arch. Obsolete.

The upper or exterior curve of an arch; esp. the upper curve of the voussoirs or stones which immediately form the arch. Cf. intrados, n.

The lower or interior curve of an arch; esp. the lower curve of the voussoirs or stones which immediately form the arch. Cf. extrados, n.

Architecture. The side of an arch between the crown and the piers, the flank; = hance, n. 3. Hence the corresponding part of any arched figure.

a wedge-shaped brick or stone used in the construction of arches. Arch-stone State, the ‘Keystone State’, Pennsylvania.

spec. in Architecture: see quot. 1875.

Occasionally used in the following senses, where quoin, n. is the ordinary modern spelling. A corner-stone; a projecting corner or angle of a…

Ornamental moulding round the exterior of an arch. Also attributive.

A stone which forms the upper part of an arched window. In quot. 1867 attributive.

A dosseret resembling a cushion pressed down by a weight.

As part of a mechanism or construction. Architecture. Each of the supports of an arch.