/ Dictionary / Index Y yestern: Meaning and Definition of Find definitions for: yes•tern Pronunciation: (yes'turn), [key] — adj. Archaic. yester. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. yestermorning yesternight 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