John, 1903–57, U.S. mathematician, born in Hungary.
British Dictionary definitions for Von Neumann
von Neumann
/vɒn ˈnjuːmən; fɒn/
noun
1.
John. 1903–57, US mathematician, born in Hungary. He formulated game theory and contributed to the development of the atomic bomb and to the development of the stored-program computer (von Neumann machine)