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 But any planetarium app with satellite data will work. Eric Adams, Popular Mechanics, "How to Track and Photograph Secret Spacecraft," 10 Nov. 2019 The event will also feature an indoor planetarium in the Courtyard Marriott Houston Springwoods Village to avoid the heat or inclement weather. Chevall Pryce, Houston Chronicle, "Northwest Houston community celebrating Apollo 11 with family fun and NASA researcher," 12 July 2019 The park has an astronomy program for visitors that includes full-dome movies at the planetarium, a meteorite collection, telescopic observation at day and night, and nightly guided tours. Scott Stulberg, National Geographic, "These are the world’s best stargazing spots," 29 Oct. 2019 The Amorphophallus titanum plant, named Little Eva, will be on display on the patio of OCC’s planetarium from 10 a.m. to 3 p.m. Wednesday through Aug. 16. Daily Pilot, "Around Town: George Thorogood, Live and Bush among headliners of upcoming Pacific Amphitheatre concerts," 8 Aug. 2019 The planetarium shows were the clear priority, as people filled the 54 seats for each of the five shows. Linda Gandee/special To,, "50th anniversary of moon landing celebrated at Lake Erie Nature and Science Center in Bay Village," 22 July 2019 Plans included an aviation center at what was then known as Forman Field — today part of Davie’s education complex — and a planetarium. Sylvia Gurinsky,, "Emil Buehler took Broward County to the stars | Opinion," 22 Aug. 2019 Boston Black moon here: rare, visually underwhelming North America will experience a black moon Wednesday night, a phenomenon that only occurs once every couple of years, said Nick Ferreri, the planetarium fellow at the Museum of Science., "New England news in brief," 31 July 2019 Outside, there's a live DJ, a rocket bounce house and other kids activities, and food trucks; inside, there's 20-minute planetarium shows at noon, 1 and 2 p.m., a chance to check out early maps of the moon, and more. Chris Foran, Milwaukee Journal Sentinel, "6 things you should be doing in Milwaukee this weekend, from Festa Italiana to the moon landing," 18 July 2019

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

4 Dec 2019

Cite this Entry

“Planetarium.” The Dictionary, Merriam-Webster Inc., Accessed 14 December 2019.

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More Definitions for planetarium


How to pronounce planetarium (audio)

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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