Fig. e e.—Perpendicular Window-head.
Fig. f f.—Late Perpendicular Window-head.
Transept.—The arms of a church or cathedral which cross the line of the nave.
Transition.—The architecture of a period coming between and sharing the characteristics of two distinctly marked styles or phases of architecture, one of which succeeded the other.
Transom.—A horizontal bar (usually of stone) across a window or panel.
Trefoil.—A three-leaved or three-lobed form found constantly in the heads of windows and in other situations where tracery is employed.