'Planetarium' definitions:

Definition of 'planetarium'

From: WordNet
noun
A building housing an instrument for projecting the positions of the planets onto a domed ceiling
noun
An optical device for projecting images of celestial bodies and other astronomical phenomena onto the inner surface of a hemispherical dome
noun
An apparatus or model for representing the solar systems

Definition of 'Planetarium'

From: GCIDE
  • Planetarium \Plan`e*ta"ri*um\, n. [NL.: cf. F. plan['e]taire. See Planetary.] An orrery. See Orrery. [1913 Webster]

Synonyms of 'planetarium'

From: Moby Thesaurus