Chthonic literally means "subterranean", but the word in English describes deities or spirits of the underworld, especially in the Ancient Greek religion.

What does the term chthonic mean?

chthonic \THAH-nik\ adjective. : of or relating to the underworld : infernal. Examples: "In Greek mythology, the Eumenides were three goddesses tasked with protecting the cause of justice.…

What does chthonic mean Greek mythology?

chthonic, of or relating to earth, particularly the Underworld. Chthonic figures in Greek mythology included Hades and Persephone, the rulers of the Underworld, and the various heroes venerated after death; even Zeus, the king of the sky, had earthly associations and was venerated as Zeus Chthonius.