Antichthon

noun

noun ·Rare ·Advanced level

Definitions

Noun
  1. 1
    A hypothetical Earth on the opposite side of the Sun. obsolete

    "It is curious at least, that his Philosophy obliged Pythagoras, to make the Solar System #61;10, tho' his imperfect Astrognosy reduced him to the shift of including the moon, and imagining an Antiχθων ["anti-earth, anti-world"] and taking the whole as a completory Unit—Sun, Mer[cury,] Ven[us,] Earth, Moon, Mars, Jupiter, Saturn, Antichthon #61;9#43; Solar Syst[em] #61;1#61;10"

Example

More examples

"It is curious at least, that his Philosophy obliged Pythagoras, to make the Solar System #61;10, tho' his imperfect Astrognosy reduced him to the shift of including the moon, and imagining an Antiχθων ["anti-earth, anti-world"] and taking the whole as a completory Unit—Sun, Mer[cury,] Ven[us,] Earth, Moon, Mars, Jupiter, Saturn, Antichthon #61;9#43; Solar Syst[em] #61;1#61;10"

Etymology

From Ancient Greek ἀντίχθων (antíkhthōn), from ἀντί (antí, “against, opposite”) + χθών (khthṓn, “Earth”).

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.