- earth [ʉrth]n.[ME erthe < OE eorthe, akin to Ger erde < IE base * er- > Gr era, earth, Welsh erw, field]1. [often E-] the planet that we live on; terrestrial globe: it is the fifth largest planet of the solar system and the third in distance from the sun: diameter, c. 12,760 km ( c. 7,930 mi); period of revolution, one earth year; period of rotation, 24 hours; one satellite; symbol, ♁: often with the2. this world, as distinguished from heaven and hell3. all the people on the earth4. land, as distinguished from sea or sky; the ground5. the soft, granular or crumbly part of land; soil; ground6. Old Poet.a) the substance of the human bodyb) the human bodyc) the concerns, interests, etc. of human life; worldly matters7. the hole of a burrowing animal; lair8. Obs. a land or country9. Chem. any of the metallic oxides, formerly classed as elements, which are reduced with difficulty to an alkaline-earth metal, rare-earth element, or certain other metals10. Elec. [Brit.] Elec. Brit. GROUND1vt.1. to cover (up) with soil for protection, as seeds or plants2. to chase (an animal) into a hole or burrowvi.to hide in a burrow: said of a fox, etc.——————come back to earth or come down to earthto stop being impractical; return to reality——————down to earth1. practical; realistic2. sincere; without affectation——————go to earthChiefly Brit. to go into hiding——————on earthof all things: an intensive used mainly after interrogative pronouns [what on earth do you mean?]——————run to earth [< use in fox hunting]1. to hunt down2. to find by searchSYN.- EARTH is applied to the globe or planet we live on, but in religious use is opposed to heaven or hell; UNIVERSE refers to the whole system of planets, stars, space, etc. and to everything that exists in it; WORLD is equivalent to EARTH, esp. as relates to human activities, but is sometimes a generalized synonym for UNIVERSE
English World dictionary. V. Neufeldt. 2014.