Read the dictionary definition of kingdom. All definitions for this word.
1. a basic group of natural objects
2. the highest taxonomic group into which organisms are grouped; one of five biological categories: Monera or Protoctista or Plantae or Fungi or Animalia
3. a monarchy with a king or queen as head of state
4. the domain ruled by a king or queen
5. a country with a king as head of state
6. a domain in which something is dominant
1. the untroubled kingdom of reason
2. a land of make-believe
3. the rise of the realm of cotton in the south
See also:
Merriam-Webster definition of kingdom