1. extremely dark, gloomy, or forbidding
Usage: literary
2. relating to the river Styx in Greek mythology
Usage: mythological; literary

Examples

• The cave’s stygian depths seemed to swallow all light.
• A stygian darkness enveloped the abandoned mansion.
• The storm clouds created a stygian atmosphere over the city.
• He descended into the stygian gloom of the basement.
• The poet described the stygian waters of the underworld.
• The forest path disappeared into stygian shadows.