Ridge: the highest point or line of a roof.
Ridge Rib: See Rib.
Rococo: style of decoration, distinguished by rock-work, shells, scrolls, etc., which originated in France during the period of the Regency and Louis XV.
Rood-loft: a gallery over the entrance to the chancel, in which stood a cross or rood. Used for reading portions of the service and also in the performance of miracle plays.
Rose-window or Wheel-window: a circular window, whose Mullions (which see) converge toward the centre.
Rostral Column: a column decorated with imitations of the prows (rostra) of vessels; used by the Romans to commemorate a naval victory.
Rubble: Rubblework: masonry composed of irregularly shaped or broken stone, whether mixed or not with cement; also the fragments of stone, mixed with cement, used to fill in the thickness of a wall, between the two faces of dressed stone.
Rustication: treatment of masonry with deeply recessed joints, grooved or beveled; the surface of the stone is sometimes made rough.
[S]cotia: a concave moulding, frequently used in the base of Classic columns.
Screen: a partition of wood, metal, marble, or stone, separating the choir from the nave. Latin cancellus; hence by corruption the English term, Chancel.