/ˈmesəsfɪə(r);ˈmez-||; ˈmɛsoˌsfɪr/noun [sing] the mesosphere the region of the earth's atmosphere between about 50 and 80 kilometres above the surface of the earth, above the STRATOSPHERE and below the THERMOSPHERE 中间层，中气层（地球大气层的区域，离地面50至80公里，介于平流层和热层之间）