/ Dictionary / Index U undies: Meaning and Definition of Find definitions for: un•dies Pronunciation: (un'dēz), [key] — n.pl. women's or children's underwear. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: undies (Thesaurus) undid undigestible Related Content Daily Word Quiz: acquiesce Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language