abstract:A pendentive is a constructive device permitting the placing of a circular dome over a square room or an elliptical dome over a rectangular room.The Columbia Encyclopedia, sixth edition The pendentives, which are triangular segments of a sphere, taper to points at the bottom and spread at the top to establish the continuous circular or elliptical base needed for the dome.
N
any of four triangular sections of vaulting with concave sides, positioned at a corner of a rectangular space to support a circular or polygonal dome 穹隅