- the act or fact of preceding; precedence.
- the motion of the rotation axis of a rigid body, as a spinning top, when a disturbing torque is applied while the body is rotating such that the rotation axis describes a cone, with the vertical through the vertex of the body as axis of the cone, and the motion of the rotating body is perpendicular to the direction of the torque.
- Astronomy.
- the slow, conical motion of the earth's axis of rotation, caused by the gravitational attraction of the sun and moon, and, to a smaller extent, of the planets, on the equatorial bulge of the earth.
- precession of the equinoxes.
- the act of preceding
- See precession of the equinoxes
- the motion of a spinning body, such as a top, gyroscope, or planet, in which it wobbles so that the axis of rotation sweeps out a cone
