1. A political or territorial unit ruled by a sovereign.
a. The eternal spiritual sovereignty of God or Christ.
b. The realm of this sovereignty.
3. A realm or sphere in which one thing is dominant: the kingdom of the imagination.
4. In the Linnean taxonomic system, the highest taxonomic category into which organisms are grouped, based on fundamental similarities and common ancestry. One widely used taxonomic system designates five or six such groups: animals, plants, fungi, protists, and prokaryotes (often divided into bacteria and archaea). Other systems divide organisms into domains (eukaryotes, bacteria, and archaea) that replace or rank above kingdoms.
5. One of the three main divisions (animal, vegetable, and mineral) into which natural organisms and objects have traditionally been classified.
[Middle English, from Old English cyningdōm : cyning, king; see KING + -dōm, -dom.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.