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English definition of “planet”

planet

noun [C]  /ˈplæn·ɪt/ us  
earth science an extremely large, round mass of matter, such as Earth or Mars, that moves in a circular path around the sun or another star
planetary
adjective [not gradable]  /ˈplæn·əˌter·i/ us  
earth science planetary scientists
(Definition of planet from the Cambridge Academic Content Dictionary © Cambridge University Press)
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