kingdom

Etymology

From Middle English kingdom, kyngdom, from Old English cyningdōm from Proto-Germanic *kuningadōmaz, equivalent to king + -dom. Cognate with Scots kingdom, West Frisian keuningdom, Dutch koningdom, German Königtum, Danish kongedømme, Swedish kungadöme, and Icelandic konungdómur.

noun

1. A realm having a king and/or queen as its actual or nominal sovereign.
2. A realm, region, or conceptual space where something is dominant.
   the kingdom of thought
   the kingdom of the dead
3. (taxonomy) A rank in the classification of organisms, below domain and above phylum; a taxon at that rank (e.g. the plant kingdom, the animal kingdom).