New·ton (ntn, nytn), Sir Isaac 1642-1727.
English mathematician and scientist who developed the techniques of calculus and formulated the theory of universal gravitation, a corpuscular theory of light, and three laws of motion. His theory of gravitation, presented in Principia Mathematica (1687), was supposedly inspired by the sight of a falling apple.
(click for a larger image)Isaac Newton
1726 portrait by
Enoch Seeman (1694-1744)
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2019 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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