nutation

Definitions

General Science

  • noun an uneven rotation of a spinning object, especially a planet, caused by a temporary change in the position of its axis

Astronomy

  • Tiny, gyroscope-like motion of the Earth’s polar axis, which occurs on a 19-year cycle and is caused by variations in the solar and lunar gravitational forces acting on the Earth

Electronics

  • A periodic variation, such as a wobble, in a spinning or rotating body, such as a gyroscope.

Medical

  • noun involuntary nodding of the head
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