Pylon: a doorway, flanked by two Truncated Pyramids with oblong bases. See Pyramid.
Pyramid: a structure of masonry, generally with a square base, with triangular sides meeting at an apex. When the sides mount in steps it is distinguished as a Stepped Pyramid. When the sides end abruptly, before reaching the apex, it is called a Truncated Pyramid.
[Q]uadriga: a four horse chariot.
Quatrefoil: See Foil.
Quatrocento: Italian term for the period called in English the fifteenth century.
Queen-Post: in timbered roof construction, one of the two posts resting on one of the Tie-beams, at equal distance from the centre, to reinforce the rafters. See King-Post.
Quoin: specifically, one of the large, square stones at the angle (coign) of a building.
[R]amp: an inclined approach to a terrace or platform, usually parallel to the sustaining wall of the latter.
Rayonnant: (“radiating”): used to distinguish the second period of French Gothic (Fourteenth Century); from the characteristic radiating or “wheel” tracery of the rose-windows. Compare “Decorated.”
Refinements: a term applied to the instances in Hellenic, Byzantine, and Gothic architecture of deviations from geometrical symmetry, to secure a more flowing, rhythmic beauty. See Asymmetries.