Pen*den"tive (?), n. [F. pendentif, fr. L. pendere to hang.] Arch. (a)
The portion of a vault by means of which the square space in the middle of a building is brought to an octagon or circle to receive a cupola.
(b)
The part of a groined vault which is supported by, and springs from, one pier or corbel.
© Webster 1913.