superbillionaire
noun
su·per·bil·lion·aire ˌsü-pər-ˌbi(l)-yə-ˈner 
-ˈbi(l)-yə-ˌner
plural superbillionaires
: a person whose wealth amounts to many billions (as of dollars or pounds)
… established the archetype of the shady superbillionaire who buys a soccer team to use as his personal plaything.
Brian Phillips
Brian Phillips
Word History
First Known Use
1924, in the meaning defined above