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Related to precessional: precesses
1. The act or state of preceding; precedence.
2. Physics The motion of the axis of a spinning body, such as the wobble of a spinning top, when there is an external force acting on the axis.
a. Precession of the equinoxes.
b. A slow gyration of the earth's rotational axis around the pole of the ecliptic, caused by the gravitational pull of the sun, moon, and other planets on the earth's equatorial bulge.
[Late Latin praecessiō, praecessiōn-, from Latin praecessus, past participle of praecēdere, to go before; see precede.]