/ Dictionary / Index Y yestermorning: Meaning and Definition of Find definitions for: yes•ter•morn•ing Pronunciation: (yes'tur-môr'ning), [key] — Archaic. Archaic. —n. yesterday morning. —adv. during yesterday morning. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. yesterevening yestern Related Content Daily Word Quiz: benevolent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language