Breadcrumb Home > Dictionary > Index W William: Meaning and Definition of Find definitions for: Wil•liam Pronunciation: (wil'yum), [key] — n. a word formerly used in communications to represent the letter W. a male given name: from Germanic words meaning “will” and “helmet.” Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. willful William I ✖ Related Content Daily Word Quiz: glissade Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language