earthboundEnglishOxford New American Dictionaryearthbound /ˈərTHˌbound, ˈərθˌbaʊnd / ▸ adjective 1 attached or restricted to the earth: a flightless earthbound bird. 2 attached or limited to material existence as distinct from a spiritual or heavenly one: her earthbound view of the sacrament. ▪ lacking in imaginative reach or drive: an earthbound performance. 3 moving toward the earth: an earthbound spaceship.