Crossword Dictionary

What's The Definition Of Acceleration?

\Ac*cel`er*a"tion\, n. [L. acceleratio: cf. F. acc['e]l['e]ration.] The act of accelerating, or the state of being accelerated; increase of motion or action; as, a falling body moves toward the earth with an acceleration of velocity; -- opposed to {retardation}. A period of social improvement, or of intellectual advancement, contains within itself a principle of acceleration. --I. Taylor. (Astr. & Physics.) {Acceleration of the moon}, the increase of the moon's mean motion in its orbit, in consequence of which its period of revolution is now shorter than in ancient times. {Acceleration} and {retardation of the tides}. See {Priming of the tides}, under {Priming}. {Diurnal acceleration of the fixed stars}, the amount by which their apparent diurnal motion exceeds that of the sun, in consequence of which they daily come to the meridian of any place about three minutes fifty-six seconds of solar time earlier than on the day preceding. {Acceleration of the planets}, the increasing velocity of their motion, in proceeding from the apogee to the perigee of their orbits.