Word Study
billionaire
WORDNET DICTIONARY
Noun billionaire has 1 sense
OXFORD DICTIONARY
billionaire, n. a person possessing over a billion pounds, dollars, etc.
Etymology
after MILLIONAIRE
THESAURUS
billionaire
Daddy Warbucks, bloated plutocrat, capitalist, fat cat, man of means, man of substance, man of wealth, millionaire, moneybags, moneyed man, multimillionaire, nabob, parvenu, plutocrat, rich man, richling, warm man, wealthy man
For further exploring for "billionaire" in Webster Dictionary Online