/ Dictionary / Index W willy wagtail: Meaning and Definition of Find definitions for: wil'ly wag'tail Pronunciation: [key] a large black-and-white bird, Rhipidura leucophrys, of Australia and New Guinea, having bristles around the upper bill and a long, fanlike tail. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. willywacks willy-willy Related Content Daily Word Quiz: belligerent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language