planetarium
noun
plan·e·tar·i·um
ˌpla-nə-ˈter-ē-əm 
plural planetariums or planetaria
ˌpla-nə-ˈter-ē-ə
1
: a model or representation of the solar system
2
a
: 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
For the most accurate location-specific information, consult online planetariums like Stellarium.
—
Jamie Carter, Forbes.com, 21 July 2025
In 1953 Indianapolis businessman James Irving Holcomb, vice president of the school's board of trustees, donated $250,000 to the school to build an observatory and planetarium to mark Butler's centennial celebration.
—Indianapolis Star, IndyStar, 2 July 2025
For a list of all the planetariums to visit to view the meteor showers, check out our guide.
—Tiffany Acosta, AZCentral.com, 8 July 2025
The opto-mechanical planetarium projector remains a technological wonder of the modern world.
—Martin Bush, Space.com, 5 July 2025
See All Example Sentences for planetarium
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Jamie Carter, Forbes.com, 21 July 2025
In 1953 Indianapolis businessman James Irving Holcomb, vice president of the school's board of trustees, donated $250,000 to the school to build an observatory and planetarium to mark Butler's centennial celebration.
—Indianapolis Star, IndyStar, 2 July 2025
For a list of all the planetariums to visit to view the meteor showers, check out our guide.
—Tiffany Acosta, AZCentral.com, 8 July 2025
The opto-mechanical planetarium projector remains a technological wonder of the modern world.
—Martin Bush, Space.com, 5 July 2025
See All Example Sentences for planetarium
Cite this Entry
“Planetarium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/planetarium. Accessed 29 Jul. 2025.
Copy CitationKids Definition
planetarium
noun
plan·e·tar·i·um
ˌplan-ə-ˈter-ē-əm
plural planetariums or planetaria
-ē-ə
1
: a device that projects images of heavenly bodies on a ceiling shaped like a dome
2
: a building or room housing a planetarium
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