Newton's law of gravitation

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The law proposed by Sir Isaac Newton that expresses the force of gravitational attraction between two bodies as a function of their masses and their distance. Expressed mathematically, F = ^Gm1m2/_d² where F is the force in Newtons, m₁ and m₂ are the masses of the bodies in kilograms, G is the gravitational constant, and d is the distance between the bodies in meters.