Niebuhr, Reinhold Syllabification: (Nie·buhr, Reinhold)Pronunciation: /ˈnēˌbo͝or/Definition of Niebuhr, Reinhold (1892–1971), US theologian and political activist. Professor of Christian ethics at Union Theological Seminary 1928–60, he wrote Moral Man and Immoral Society (1932) and The Irony of American History (1952).
