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New·ton

(ntn, nytn), 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.

New·toni·an adj.

(click for a larger image)

Isaac Newton

1726 portrait by

Enoch Seeman (1694-1744)

new·ton

(ntn, nytn)

n. Abbr. N

The SI-derived unit of force required to accelerate a mass of one kilogram one meter per second per second, equal to 100,000 dynes. See Table at measurement.

[After Sir Isaac Newton.]

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:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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