Kepler, Johannes Syllabification: (Kep·ler, Johannes)Pronunciation: /ˈkeplər/Definition of Kepler, Johannes (1571–1630), German astronomer. He discovered the three laws that govern orbital motion. Derivatives KeplerianPronunciation: /kepˈli(ə)rēən/ adjective Kepler, Johannes in other Oxford dictionaries Definition of Kepler, Johannes in the British & World English dictionary