Underworld

1. n. The inferior part of mankind.
2. n. The lower of inferior world; the world which is under the heavens; the earth.
3. n. The mythological place of departed souls; Hades.
4. n. The portion of the world which is below the horizon; the opposite side of the world; the antipodes.

The word meanings were obtained from OPTED(The Online Plain Text English Dictionary), which is based on “The Project Gutenberg Etext of Webster’s Unabridged Dictionary” which is in turn based on the 1913 US Webster’s Unabridged Dictionary (See Project Gutenburg), as a text file.