realm

noun8

1. •
   an area of knowledge, work or power with a subject and rules of its own

   • the realm of physics
2. •
   A primary zoogeographical division of the earth's surface.
3. •
   A grouping of equally trusted computers managed together on a network.
4. •
   A taxonomic rank in the phylogeny of viruses, higher than kingdoms.
5. •
   A territory or state, as ruled by an absolute authority, especially by a king; a kingdom.

   • And, of this island realm, he and his companion were the undisputed sovereigns. — 1874
6. •
   An otherworldly dimension or domain — magical, ethereal, or otherwise.
7. •
   (no longer used) The spiritual state of which God is the head; the Kingdom of Heaven.
8. •
   (no longer used) A region or zone forming part of a cosmological system.