CHTHONIC Meaning of CHTHONIC in English [ '(k)θɒnɪk ](also chthonian '(k)θəʊnɪən ) ■ adjective relating to or inhabiting the underworld.OriginC19: from Gk khthōn 'earth' + -ic . Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004