Gyration

Part of speech: noun (n.)

1. The act of turning or whirling, as around a fixed center; a circular or spiral motion; motion about an axis; rotation; revolution. The gyrations of an ascending balloon. De Quincey. If a burning coal be nimbly moved round in a circle, with gyrations continually repeated, the whole circle will appear like fire. Sir I. Newton.

2. One of the whorls of a spiral univalve shell. Center of gyration. (Mech.) See under Center. -- Radius of gyration the distance between the axis of a rotating body and its center of gyration. Rankine.