An Etymological Dictionary of Astronomy and Astrophysics

Small-scale variations in the position of the Earth’s geographical poles within an irregular circle of 3 to 15 metres in diameter. It seems to result from two nearly circular components,
a seasonal variation in the mass distribution on the Earth (ice, snow, atmosphere) and movements of matter within the Earth.

See also: Named after Seth Carlo Chandler (1846-1913), the American astronomer who discovered the phenomenon; → wobble.