Meaning of counterearth

coun•ter•earth

Pronunciation: (koun'tur-ûrth"), [key]
— n.
  1. (in Pythagorean astronomy) a planet, out of sight from our part of the earth, whose shadow upon the sun and moon, cast by a central fire that is also out of sight, causes the eclipses. Also called
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.