realm of the dead; shades of the dead
A literary, somewhat archaic term for the world of the dead or the afterlife. Not used in everyday conversation; modern Japanese prefers 冥界 (めいかい) or あの世.
In classical literature, stories of visiting the realm of the dead are common.
Compound of 冥 (めい, 'dark, underworld') and 境 (きょう, 'boundary, realm'). The exact historical derivation is uncertain; it is a Sino-Japanese word used in classical and literary contexts.