1. (Science: astronomy) planet that is the third in order from the sun. It is one of the four inner or terrestrial planets of the solar system.
2. The softer inorganic matter composing part of the surface of the globe, in distinction from the firm rock; soil of all kinds, including gravel, clay, loam, and the like; sometimes, soil favorable to the growth of plants; the visible surface of the globe; the ground; as, loose earth; rich earth. Give him a little earth for charity. (Shak)
3. (Science: chemistry) Any earthy-looking metallic oxide, as alumina, glucina, zirconia, yttria, and thoria. a similar oxide, having a slight alkaline reaction, as lime, magnesia, strontia, baryta.
4. Earth is used either adjectively or in combination to form compound words; as, earth apple or earth-apple; earth metal or earth-metal; earth closet or earth-closet. Adamic earth, bitter earth, bog earth, Chian earth, etc. See Adamic, bitter, etc. Alkaline earths. See alkaline. Earth apple.
Origin: as. Eore; akin to os. Ertha, OFries. Irthe, D. Aarde, OHG. Erda, g. Erde, Icel. Jor, Sw.