/ Dictionary / Index D donkey's years: Meaning and Definition of Find definitions for: don'key's years" Pronunciation: [key] — Informal. Informal. a very long time; eons. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. donkey's tail donkey topsail Related Content Daily Word Quiz: philtrum Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language