chthonian (adj.)

word-forming element meaning "pertaining to," from Latin -anus, adjective suffix, in some cases via French -ain, -en. From PIE *-no-.

Proto-Indo-European root meaning "earth."

It forms all or part of: antichthon; autochthon; autochthonic; bonhomie; bridegroom; camomile; chameleon; chernozem; chthonic; exhume; homage; hombre; homicide; hominid; Homo sapiens; homunculus; human; humane; humble; humiliate; humility; humus; inhumation; inhume; nemo; ombre; omerta.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit ksam- "earth" (opposed to "sky"); Greek khthōn "the earth, solid surface of the earth," khamai "on the ground;" Latin humus "earth, soil," humilis "low;" Lithuanian žemė, Old Church Slavonic zemlja "earth;" Old Irish du, genitive don "place," earlier "earth."