What is Earth-color?

Earth-color definition and meaning on Dictionary terms:
(often initial capital letter) the planet third in order from the sun, having an equatorial diameter of 7926 miles (12,755 km) and a polar diameter of 7900 miles (12,714 km), a mean distance from the sun of 92.9 million miles (149.6 million km), and a period of revolution of 365.26 days, and having one satellite.
the inhabitants of this planet, especially the human inhabitants: The whole earth rejoiced.
this planet as the habitation of humans, often in contrast to heaven and hell: to create a hell on earth.
the surface of this planet: to fall to earth.
the solid matter of this planet; dry land; ground.

soil and dirt, as distinguished from rock and sand; the softer part of the land.
the hole of a burrowing animal; lair.
Chemistry. any of several metallic oxides that are difficult to reduce, as alumina, zirconia, and yttria.Compare alkaline earth, rare earth.
Also called earth color. Fine Arts. any of various pigments consisting chiefly of iron oxides and tending toward brown in hue.
Chiefly British Electronics. a ground.
Archaic. a land or country.

verb (used with object)
Chiefly British Electronics. to ground.