planetarium

play
noun plan·e·tar·i·um \ˌpla-nə-ˈter-ē-əm\

Definition of planetarium

plural

planetariums

or

planetaria

play \ˌpla-nə-ˈter-ē-ə\
  1. 1 :  a model or representation of the solar system

  2. 2a :  an optical device for projecting various celestial images and effectsb :  a building or room housing such a projector

1860

First Known Use of planetarium

1860


PLANETARIUM Defined for English Language Learners

planetarium

play
noun plan·e·tar·i·um \ˌpla-nə-ˈter-ē-əm\

Definition of planetarium for English Language Learners

  • : a building or room in which images of stars, planets, etc., are shown on a high, curved ceiling


PLANETARIUM Defined for Kids

planetarium

play
noun plan·e·tar·i·um \ˌpla-nə-ˈter-ē-əm\

Definition of planetarium for Students

  1. :  a building in which there is a device for projecting the images of heavenly bodies on a ceiling shaped like a dome



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