Kep·ler (kĕplər), Johannes 1571-1630.
German astronomer and mathematician whose three laws describing the elliptical orbits of celestial bodies provided a basis for Isaac Newton's theory of gravitation.
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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