plan·e·tar·i·um | \ ˌpla-nə-ˈter-ē-əm \
plural planetariums or planetaria\ˌpla-nə-ˈter-ē-ə \

Definition of planetarium 

1 : a model or representation of the solar system

2a : an optical device for projecting various celestial images and effects

b : a building or room housing such a projector

Examples of planetarium in a Sentence

Recent Examples on the Web

Now known as the Daniel M. Soref Dome Theater & Planetarium, the facility is, more or less, back to the original idea: a planetarium. Chris Foran, Milwaukee Journal Sentinel, "Milwaukee once tried to launch its own space center. It never took off.," 12 June 2018 During the day, the planetarium still holds traditional space science shows on the solar system, NASA missions, and the night sky. Cristela Guerra,, "At the planetarium, drag shows that are out of this world," 23 June 2018 The planetarium is scheduled to be erected again this year, librarians said. Pioneer Press,, "Tomes aren't the only offerings at local public libraries: Officials," 4 May 2018 With Push the Feeling DJs; pop-up beer garden; extended aquarium/exhibition hours; The Plant Ladym and Sutro Stewards, plant talks; planetarium screening; cocktails., "Exhibits listings," 12 July 2018 The four-day festival includes a writing carnival outside the Franklin Institute, a soul-music dance party at the museum planetarium, a keynote talk, and a gospel breakfast. Grace Dickinson,, "Mighty Writers launches a festival of its own: MightyFest, coming this fall," 10 July 2018 Enter San Diego’s Fleet Science Center planetarium. Diane Bell,, "Mermaid's disappearance from OB rock creates waves," 15 June 2018 This may not be a Wisconsin museum, but Chicago is close enough and spending the night in a planetarium is cool enough to be worth the drive for an Astro-overnight. Amy Schwabe, Milwaukee Journal Sentinel, "Night at the museum: Have your next slumber party at one of these three museums," 20 Oct. 2017 With 4505 Meats, smoker demo/discussion; The Perennial, roast vegetables technique discussion; Stanford Neuroscience, food science; extended aquarium/exhibition hours; planetarium screening; cocktails. 6-10 p.m. Thurs., July 5., "Exhibits listings," 28 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'planetarium.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of planetarium

1860, in the meaning defined at sense 1

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Last Updated

28 Aug 2018

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Time Traveler for planetarium

The first known use of planetarium was in 1860

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English Language Learners Definition of planetarium

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


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

Kids Definition of planetarium

: 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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