Eu·clid (yklĭd) Third century BC.
Greek mathematician who applied the deductive principles of logic to geometry, thereby deriving statements from clearly defined axioms. His Elements remained influential as a geometry textbook until the 19th century.
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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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