plan·​e·​tar·​i·​um | \ ˌpla-nə-ˈter-ē-əm How to pronounce planetarium (audio) \
plural planetariums or planetaria\ ˌpla-​nə-​ˈter-​ē-​ə How to pronounce planetaria (audio) \

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

America’s first planetarium is setting sights on reaching astronomy buffs beyond its Lake Michigan confines. Vickie Snow Jurkowski, Daily Southtown, "Adler Planetarium bringing telescopes to a library, park or taproom near you this summer," 20 June 2018 Instead, go to a planetarium for a night-time view of the sky sans the frigid temps. 14. Kelsey Stiegman, Seventeen, "14 Cheap Valentine's Day Date Ideas That Are Actually Fun," 19 Nov. 2018 Museums, planetariums and libraries across the U.S. held viewing parties to watch the events unfold at JPL. Marcia Dunn, The Seattle Times, "Mars touchdown: NASA spacecraft survives supersonic plunge," 28 Nov. 2018 The full museum opened to the public in 1950 and has been updated over the years to include the planetarium that our young wish-listers find themselves in. Lauren Hubbard, Town & Country, "Two Kids Explore the Vanderbilt Estate in This New Maisonette Video," 26 Nov. 2018 The structure was meant to serve as a planetarium, restaurant, and scenic overlook—a day-trip destination for people who would head to the building as a tourist attraction and then return home. Megan Barber, Curbed, "Lost Frank Lloyd Wright buildings reimagined in new renderings," 5 Nov. 2018 These ranged from whether the original annexation of Hawaii was constitutional (and thus the state government valid) to whether the retired judge's family membership to a planetarium constituted a conflict of interest. John Timmer, Ars Technica, "Hawaiian Supreme Court gives go-ahead to giant telescope," 1 Nov. 2018 As curator of Griffith Observatory, Danly develops exhibits, planetarium shows, and public programs about astronomy. Hans Aschim, Harper's BAZAAR, "Three Women in Science Who Broke the Glass Ceiling," 5 Oct. 2018 When Tech Meets Art, futurism discussion; Cool Neon, programmable LED talk/exhibit; extended aquarium/exhibition hours; Incoming, planetarium showing; cocktails. Chronicle Staff Report, San Francisco Chronicle, "Exhibits listings," 26 Apr. 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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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 How to pronounce planetarium (audio) \

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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Rhyming Dictionary: Words that rhyme with planetarium

Spanish Central: Translation of planetarium

Nglish: Translation of planetarium for Spanish Speakers Encyclopedia article about planetarium

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What made you want to look up planetarium? Please tell us where you read or heard it (including the quote, if possible).


to speak slightingly about or to degrade

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