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
Example Sentences
Recent Examples on the Web Instead, the pages unfold to become amazing things, like a working planetarium that can project constellations onto the walls, a speaker that can amplify sound or a playable musical instrument. 
Marisa Lascala, Good Housekeeping, 6 Sep. 2022 The Bible-themed museum allows visitors to venture through biblical history as well as visit the botanical gardens, a planetarium, zoo and zipline course. Cathi Douglas, San Diego Union-Tribune, 6 Aug. 2022 The Adler Planetarium, the first planetarium in the western hemisphere, opens. Chicago Tribune, 26 June 2022 Eight of its 23 galleries, an upgraded planetarium, store and cafe will welcome visitors for the first time since construction closed the building six months ago. Peggy Mcglone, Washington Post, 2 Aug. 2022 For the summer’s first show in June, a technical issue at the planetarium forced the group to move to the museum’s Mugar Omni Theater. Tristram Lozaw, BostonGlobe.com, 11 July 2022 Presented by American Express and produced by Superfly, the audiovisual planetarium spectacle will take place in New York City’s Cipriani 25 Broadway, with shows starting every two hours 10-8 p.m. from Saturday to Sunday. Hannah Dailey, Billboard, 11 July 2022 The observatory and planetarium would open two years later. Elvia Limón, Los Angeles Times, 21 June 2022 Black Hole Initiative, with visuals designed by the MOS’s planetarium team. Karen Campbell, BostonGlobe.com, 21 June 2022 See More
Marisa Lascala, Good Housekeeping, 6 Sep. 2022 The Bible-themed museum allows visitors to venture through biblical history as well as visit the botanical gardens, a planetarium, zoo and zipline course. Cathi Douglas, San Diego Union-Tribune, 6 Aug. 2022 The Adler Planetarium, the first planetarium in the western hemisphere, opens. Chicago Tribune, 26 June 2022 Eight of its 23 galleries, an upgraded planetarium, store and cafe will welcome visitors for the first time since construction closed the building six months ago. Peggy Mcglone, Washington Post, 2 Aug. 2022 For the summer’s first show in June, a technical issue at the planetarium forced the group to move to the museum’s Mugar Omni Theater. Tristram Lozaw, BostonGlobe.com, 11 July 2022 Presented by American Express and produced by Superfly, the audiovisual planetarium spectacle will take place in New York City’s Cipriani 25 Broadway, with shows starting every two hours 10-8 p.m. from Saturday to Sunday. Hannah Dailey, Billboard, 11 July 2022 The observatory and planetarium would open two years later. Elvia Limón, Los Angeles Times, 21 June 2022 Black Hole Initiative, with visuals designed by the MOS’s planetarium team. Karen Campbell, BostonGlobe.com, 21 June 2022 See More Word History
First Known Use
1860, in the meaning defined at sense 1
Kids Definition
planetarium
noun
plan·e·tar·i·um ˌpla-nə-ˈter-ē-əm
: a building in which there is a device for projecting the images of heavenly bodies on a ceiling shaped like a dome