From Longman Dictionary of Contemporary Englishplanetariumplan‧e‧tar‧i‧um /ˌplænəˈteəriəm $ -ˈter-/ noun [countable] HAa building where lights on a curved ceiling show the movements of planets and stars
Examples from the Corpus
planetarium• But take them to a planetarium or a science show and watch their little eyes light up.• A mobile, inflatable planetarium costing £9,000 will now be used in the region by up to 10,000 pupils each year.• It was only incidentally a timepiece. primarily it was a mechanical representation of the universe, a kind of planetarium.• Or sit in a tiny planetarium for an introduction to the rudiments of stellar navigation.• I shall never never never forget your back yard, planetarium and ham radio shed.Origin planetarium (1700-1800) Modern Latin Latin planeta; → PLANET