Stygian

/ˈstɪʤiən/

Something that's Stygian is dark, murky, and probably a little melancholy. Your walk home from the bus stop might feel Stygian on a foggy, moonless night.

When you describe something as Stygian, you're comparing it to the murky and terrible river Styx, which flows through the underworld in ancient Greek mythology. The word itself comes from the Greek word Stygios, from Styx, which literally means "the hateful." Some related words in Greek are stygos, "hatred," and stygnos, "gloomy." That should give you a good idea of the way a Stygian library, alley, or cave looks and feels — dismal and dark.

Definitions of Stygian

1. adjective

   dark and dismal as of the river Styx in Hades
   “"upon those roseate lips a Stygian hue"-Wordsworth”

   synonyms: Acheronian, Acherontic

   dark

   devoid of or deficient in light or brightness; shadowed or black
2. adjective

   dark and gloomy
   synonyms: tenebrific, tenebrious, tenebrous

   dark

   devoid of or deficient in light or brightness; shadowed or black
3. adjective

   hellish
   “"Hence loathed Melancholy.../In Stygian cave forlorn"- Milton”

   synonyms:

   infernal

   being of the underworld