Euclid

n. (c300 B.C.), Greek mathematician, father of Euclidean geometry

Euclid (Greek: ), also known as Euclid of Alexandria, "The Father of Geometry" was a Greek mathematician of the Hellenistic period who flourished in Alexandria, Egypt, almost certainly during the reign of Ptolemy I (323 BC-283 BC). His Elements is the most successful textbook in the history of mathematics. In it, the principles of Euclidean geometry are deduced from a small set of axioms. Euclid's method of proving mathematical theorems by logical deduction from accepted principles remains the backbone of all mathematics, imbuing that field with its characteristic rigor.
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Noun
1. Greek geometer (3rd century BC)
(hypernym) geometer, geometrician

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n. Euclid, (c300 B.C.) Greek mathematician, father of Euclidean geometry