'antichthon' originates from Greek, specifically the components 'anti-' and 'khthōn' (Greek 'ἀντί' + 'χθών'), where 'anti-' meant 'opposite' and 'khthōn' meant 'earth' or 'ground'.

'antichthon' comes from classical Greek 'ἀντίχθων' (antíkhtōn), passed into scholarly Latin/Neo-Latin forms and was adopted into English in discussions of ancient cosmologies and classical literature as 'antichthon'.

Initially, it meant 'opposite earth' in the literal cosmological sense; over time its use narrowed and became chiefly literary, historical, or scholarly to denote a 'counter-Earth' or antipodal counterpart rather than a practical astronomical body.