| 1. | (often initial capital letter ) the planet third in order from the sun, having an equatorial diameter of 7926 mi. (12,755 km) and a polar diameter of 7900 mi. (12,714 km), a mean distance from the sun of 92.9 million mi. (149.6 million km), and a period of revolution of 365.26 days, and having one satellite. |
| 2. | the inhabitants of this planet, esp. the human inhabitants: The whole earth rejoiced. |
| 3. | this planet as the habitation of humans, often in contrast to heaven and hell: to create a hell on earth. |
| 4. | the surface of this planet: to fall to earth. |
| 5. | the solid matter of this planet; dry land; ground. |
| 6. | soil and dirt, as distinguished from rock and sand; the softer part of the land. |
| 7. | the hole of a burrowing animal; lair. |
| 8. | Chemistry. any of several metallic oxides that are difficult to reduce, as alumina, zirconia, and yttria. Compare alkaline earth, rare earth. |
| 9. | Also called earth color. Fine Arts. any of various pigments consisting chiefly of iron oxides and tending toward brown in hue. |
| 10. | Chiefly British Electronics. a ground. |
| 11. | Archaic. a land or country. |
| 12. | Chiefly British Electronics. to ground. |
| 13. | move heaven and earth. heaven (def. 7). |
| 14. | on earth, in the world: Where on earth have you been? |
| 15. | run to earth,
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The planet on which we live — the third planet from the sun.
Note: The Earth was formed at the same time as the sun, about 4.6 billion years ago.
Note: It consists of an inner core made of iron and nickel, an outer core of liquid metal, a mantle, and, on the outside, a crust.
Note: The surface of the solid Earth is in a state of constant change as the rock is moved around by the processes of plate tectonics.
Note: On the Earth's surface, the oceans and the continents form the stage on which the evolution of life takes place. The atmosphere above the surface circulates, producing the daily weather.
earth (ûrth)
n.
Any of several metallic oxides, such as alumina or zirconia, from which it is difficult to remove oxygen. No longer in technical use.