/ Dictionary / Index U Uniondale: Meaning and Definition of Find definitions for: Un•ion•dale Pronunciation: (yn'yun-dāl"), [key] — n. a town on W Long Island, in SE New York. 20,016. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Union City Union Day Related Content Daily Word Quiz: eureka Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language