noun, plural planetariums, planetaria [plan-i-tair-ee-uh] .
an apparatus or model representing the planetary system.
a device that produces a representation of the heavens by the use of a number of moving projectors.
the building or room in which such a device is housed.

1765–75; < Neo-Latin, noun use of neuter of Latin planētārius planetary; cf. -arium Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
Cite This Source Link To planetarium
World English Dictionary
planetarium (ˌplænɪˈtɛərɪəm)
n , pl -iums, -ia
1.  an instrument for simulating the apparent motions of the sun, moon, and planets against a background of stars by projecting images of these bodies onto the inside of a domed ceiling
2.  a building in which such an instrument is housed
3.  a model of the solar system, sometimes mechanized to show the relative motions of the planets

Collins English Dictionary - Complete & Unabridged 10th Edition
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
Cite This Source
Word Origin & History

1734, "orrery," Mod.L., from L.L. planeta (see planet) + L. -arium "a place for." Mod. sense of "device for projecting the night sky onto the interior of a dome" is attested from 1929.
Online Etymology Dictionary, © 2010 Douglas Harper
Cite This Source
Example sentences
Reach for the stars with this double-threat tabletop planetarium.
They headed back through the mammals and waited for an elevator, which would
  deliver them to the planetarium.
Enjoy our exciting science collections and space travel in our popular
At the bottom, there was a planetarium, so they would look up at the top and
  they would see stars.
Related Words
Copyright © 2014, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature