The act of turning or whirling, as around a fixed center; a circular or spiral motion; motion about an axis; rotation; revolution.

One of the whorls of a spiral univalve shell.

a single complete turn (axial or orbital); "the plane made three rotations before it crashed"; "the revolution of the earth about the sun takes one year"

the act of rotating in a circle or spiral

The circular motion of ions and electrons around magnetic field lines.