Orrery
Pronunciation : Or"re*ry
Part of Speech : n.;
Etymology : [So named in honor of the Earl of Orrery.]
Definition : Defn: 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.
pl. Orreries.
Source : Webster's Unabridged Dictionary, 1913