tartarous
/ˈtɑrtərəs/
adjective
- Relating to or resembling Tartarus, the underworld in Greek mythology; extremely dark, gloomy, or hellish.
- The storm clouds gathered in a tartarous mass, blocking all sunlight.
- The abandoned mine had a tartarous atmosphere that made explorers uneasy.
- In the poem, the hero descends into a tartarous realm of eternal darkness.