/ Dictionary / Index E ephemeron: Meaning and Definition of Find definitions for: e•phem•er•on Pronunciation: (i-fem'u-ron", -ur-un), [key] — pl. -er•a -er•ons. anything short-lived or ephemeral. items designed to be useful or important for only a short time, esp. pamphlets, notices, tickets, etc. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: ephemeron (Thesaurus) ephemeris time ephemeropteran Related Content Daily Word Quiz: secular Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language