Riemann, Bernhard Syllabification: (Rie·mann, Bernhard)Pronunciation: /ˈrēmən/Definition of Riemann, Bernhard (1826–66), German mathematician; full name Georg Friedrich Bernhard Riemann. He founded Riemannian geometry, which is of fundamental importance to both mathematics and physics. Riemann, Bernhard in other Oxford dictionaries Definition of Riemann, Bernhard in the British & World English dictionary