/ Dictionary / Index U uropygial gland: Meaning and Definition of Find definitions for: uropyg'ial gland" Pronunciation: [key] — Ornith. Ornith. a gland opening on the back at the base of the tail in most birds that secretes an oily fluid used by the bird in preening its feathers. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. uropygial uropygium 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