ACCELERA'TION, noun The act of increasing velocity or progress; the state of being quickened in motion or action. Accelerated motion in mechanics and physics, is that which continually receives accessions of velocity; as, a falling body moves towards the earth with an acceleration of velocity. It is the opposite of retardation.
Acceleration of the moon, is the increase of the moon's mean motion from the sun, compared with the diurnal motion of the earth; the moon moving with more velocity now than in ancient times - a discovery made by Dr. Halley.
The diurnal acceleration of the fixed stars, is the time by which they anticipate the mean diurnal revolution of the sun, which is nearly three minutes, fifty-six seconds.