General English

General Science

  • noun
    (written as Earth)
    the planet on which human beings developed and live
  • verb to connect an electrical device to the ground


  • noun the ground or land surface


  • (written as Earth)
    The third planet of the solar system and the only one known to house life, the Earth is also remarkable for its seas of liquid water and its oxygen-bearing atmosphere and for being very geologically active. The Earth’s equatorial radius is 6 378km, about a third of a percent more than its polar radius because of the Earth’s rotation. About 4 500 million years old, like the other planets, the Earth rotates on its axis in a day, orbits the Sun in a year and has a satellite, the Moon, which orbits it once per lunar month.


  • verb to connect an electrical appliance to a position of zero potential

Cars & Driving

  • noun the return path of an electrical system, which in a motor vehicle is provided by the metal body and chassis
  • verb to connect a circuit or a component to a metal chassis or body part, either directly or by means of a wire


  • noun a connection in a circuit representing zero potential


  • The planet earth. Also, the surface of said planet, especially the land portion.
  • synonymelectrical ground

Media Studies

  • verb to equip an electrical circuit or appliance with a connection to the ground so that current is carried safely away in the event of a fault

Origin & History of “earth”

Earth comes ultimately from an Indo-European base *er-. this produced the prehistoric Germanic noun *erthō, ancestor of German erde, Dutch aarde (whence, via early Afrikaans, English aardvark (19th c.), literally ‘earth-pig’), Swedish and Danish jord, and English earth. Related forms outside Germanic include Greek eraze ‘on the ground’ and Welsh erw ‘field’. The word’s basic range of modern senses, ‘ground’, ‘world’, and ‘soil’, all date back to the Old English period.