From Longman Dictionary of Contemporary Englishbillionairebil‧lion‧aire /ˌbɪljəˈneə◂ $ -ˈner◂/ noun [countable] someone who has more than a billion dollars or pounds
Examples from the Corpus
billionaire• Hauser is a billionaire several times over.• He was then faced during the presidential election campaign with an unexpected challenge by Ross Perot, a billionaire from Texas.• Perot, a billionaire, spent more than $ 60 million of his own money in his 1992 campaign.• Anthony Hopkins plays a bookish billionaire with a head full of unused facts.• Then billionaire Ross Perot hinted he may rejoin the presidential race as an independent.From Longman Business Dictionarybillionairebil‧lion‧aire /ˌbɪljəˈneə-ˈner/ noun [countable] someone who has assets worth at least a billion pounds, dollars etcBillionaire A. Alfred Taubman took over Sotheby’s in 1983.