A Realm

1. An abstract sphere of influence, real or imagined.
2. The domain of a certain abstraction.
3. (computing) A scope of operation in networking or security.
4. (formal or law) A territory or state, as ruled by a specific power, especially by a king.
5. (fantasy, role-playing games) An otherworldly dimension or domain — magical, ethereal, or otherwise — usually ruled or created by a mystical character.

Synonyms

• (A territory or state): country, land, kingdom
• (A sphere of activity or influence): field, province