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 planetarium (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 From colorful fashion districts, like Harajuku, to a planetarium atop a skyscraper in Ikebukuro, this version of Tokyo has a little something for everyone. Shelly Tan, Washington Post, "Five sensational vacation destinations from the virtual worlds of video games," 25 Feb. 2021 The nature center is home to a range of educational programs, a planetarium, an interactive nature discovery room and exhibits highlighting the Chesapeake Bay watershed and local forest animals, as well as several outdoor walking trails., "Guide to Howard County 2021: 30 places to take the kids," 23 Feb. 2021 Thaddeus LaCoursiere, a planetarium educator for the Bell Museum at the University of Minnesota, identified the plummeting object as a bolide, an extremely bright meteor that often explodes upon engaging Earth's atmosphere. Paul Walsh, Star Tribune, "Streaking meteor's predawn flash stars in an arresting video for Minnesota sheriff's deputy," 16 Dec. 2020 According to Facebook, the event, hosted by the planetarium’s manager and astronomer, reached more than 1.7 million interested respondents. Emily Wright,, "Visiting Venice, without leaving home," 10 Feb. 2021 The companies are some of the earliest pioneers of virtual reality, interactive VR and planetarium projection technology. Dom Difurio, Dallas News, "New tech group backed by Dallas billionaire Steve Winn emerges to deliver the theater of the future," 26 Jan. 2021 If skies are cloudy an indoor planetarium presentation will be held. Joan Rusek, cleveland, "Happy New Year, now it is time to start something new: Valley Views," 28 Dec. 2020 Not only has there been a notable uptick in subscribers, says planetarium director Dr. Schmoll, but many people who let their subscription lapse a decade or two ago have also renewed it this year. Eva Botkin-kowacki, The Christian Science Monitor, "Telescope sales and stargazers are both looking up these days," 18 Dec. 2020 For the winter season, a new production about space blizzards will take place in the museum’s planetarium. Anne Nickoloff, cleveland, "16 things to do in Cleveland this weekend, Dec. 25-27," 24 Dec. 2020

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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Time Traveler for planetarium

Time Traveler

The first known use of planetarium was in 1860

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Statistics for planetarium

Last Updated

5 Mar 2021

Cite this Entry

“Planetarium.” Dictionary, Merriam-Webster, Accessed 6 Mar. 2021.

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More Definitions for planetarium



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

More from Merriam-Webster on planetarium

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

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