ORRERY

orrery

(noun) planetarium consisting of an apparatus that illustrates the relative positions and motions of bodies in the solar system by rotation and revolution of balls moved by wheelwork; sometimes incorporated in a clock

Source: WordNet® 3.1

Etymology

Noun

orrery (plural orreries)

A clockwork model of any given solar system.

Source: Wiktionary

Or"re*ry, n.; pl. Orreries. Etym: [So named in honor of the Earl of Orrery.]

Definition: An apparatus which illustrates, by the revolution of balls moved by wheelwork, the relative size, periodic motions, positions, orbits, etc., of bodies in the solar system.

Source: Webster’s Unabridged Dictionary 1913 Edition