/ Dictionary / Index B billionaire: Meaning and Definition of Find definitions for: bil•lion•aire Pronunciation: (bil"yu-nâr', bil'yu-nâr"), [key] — n. a person who has assets worth a billion or more dollars, francs, pounds, or the like. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: billionaire (Thesaurus) billion Billiton Related Content Daily Word Quiz: perspicacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language