1. a. The land surface of the world. b. The softer, friable part of land; soil, especially productive soil.
2. Often Earth (ûrth) The third planet from the sun, having a sidereal period of revolution about the sun of 365.26 days at a mean distance of approximately 149 million kilometers (92.96 million miles), an axial rotation period of 23 hours 56.07 minutes, an average radius of 6,374 kilometers (3,959 miles), and a mass of approximately 5.974 1024 kilograms (13.17 1024 pounds).
3. The realm of mortal existence; the temporal world.
4. The human inhabitants of the world: The earth received the news with joy.
5. a. Worldly affairs and pursuits. b. Everyday life; reality: was brought back to earth from his daydreams of wealth and fame.
6. The substance of the human body; clay.
7. The lair of a burrowing animal.
8. Chiefly British. The ground of an electrical circuit.
9. Chemistry. Any of several metallic oxides, such as alumina or zirconia, that are difficult to reduce and were formerly regarded as elements.