from Wiktionary, Creative Commons Attribution/Share-Alike License
- proper n. The entrance to Hell or the underworld, or the underworld itself.
- proper n. A lake in Southern Italy.
Latin Avernus, from Ancient Greek αορνος (aornos), αϝορνος (awornos, "birdless"), from ἀ- (a-, "without") + ὄρνις (ornis, "bird"). The lack of birds was likely due to fatal gases like carbon dioxide seeping from the volcanically active lake. (Wiktionary)