Meaning

• An abstract sphere of influence, real or imagined.

• The domain of a certain abstraction.

• A scope of operation in networking or security.

• A territory or state, as ruled by a specific power, especially by a king.

• An otherworldly dimension or domain — magical, ethereal, or otherwise — usually ruled or created by a mystical character.

• A taxonomic rank in the phylogeny of viruses, higher than kingdoms.