tierceron: Meaning and Definition of

tier•ce•ron

Pronunciation: (tēr'sur-un), [key]
— n.
  1. (in a ribbed vault) a diagonal rib, other than an ogive, springing from a point of support. See illus. under.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.