Real Dictionary

earth
proper noun: Earth or the Earth is the planet on which we live. People usually say Earth when they are referring to the planet as part of the universe, and the Earth when they are talking about the planet as the place where we live.
singular noun: The earth is the land surface on which we live and move about.

earth in American English
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 satelli
to cover (up) with soil for protection, as seeds or plants
to hide in a burrow
noun: 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

earth in British English
noun: the third planet from the sun, the only planet on which life is known to exist. It is not quite spherical, being flattened at the poles, and consists of three geological zones, the core, mantle, and thin outer crust. The surface, covered with large areas