Definition of precession in English:



  • The slow movement of the axis of a spinning body around another axis due to a torque (such as gravitational influence) acting to change the direction of the first axis. It is seen in the circle slowly traced out by the pole of a spinning gyroscope.

    • ‘The binary's orbital precession, for example, is quite vigorous.’
    • ‘Einstein's theory predicts that such gyroscopes will undergo geodetic precession merely because space-time is curved in the planet's vicinity.’
    • ‘Even Newtonian physics was unable to give a complete explanation of its orbit: the direction of the axis was found to move by rather more than could be explained by precession and the gravitational attraction of the other planets.’
    • ‘As the tailwheel lifts during the takeoff run, gyroscopic precession tries to turn the plane left of centerline.’
    • ‘Of course, the anomalous precession of Mercury was already known, and general relativity could explain it.’


Late 16th century (as a term in astronomy, referring to the precession of the equinoxes): from late Latin praecessio(n-), from praecedere go before (see precede).