/ Dictionary / Index T tierceron: Meaning and Definition of Find definitions for: tier•ce•ron Pronunciation: (tēr'sur-un), [key] — n. (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. tiercel tiered Related Content Daily Word Quiz: panacea Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language