In biology, kingdom (latin: regnum, pl. regna) is the second highest taxonomic rank below domain. Kingdoms are divided into smaller groups called phyla. Traditionally, textbooks from the United States used a system of six kingdoms (Animalia, Plantae, Fungi, Protista, Archaea/Archaeabacteria, and Bacteria/Eubacteria) while textbooks in Great Britain, India, Australia, Latin America and other countries used five kingdoms (Animalia, Plantae, Fungi, Protista and Monera). Some recent classifications based on modern cladistics have explicitly abandoned the term "kingdom", noting that the traditional kingdoms are not monophyletic, i.e., do not consist of all the descendants of a common ancestor.
Classification, or taxonomy, is a system of categorizing living things. There are seven divisions in the system: (1) Kingdom; (2) Phylum or Division; (3) Class; (4) Order; (5) Family; (6) Genus; (7) Species.
Kingdom is the broadest division. While scientists currently disagree as to how many kingdoms there are, most support a five-kingdom (Animalia, Plantae, Protista, Monera, and Fungi) system. The lowest division is species, which consists of organisms that are capable of interbreeding to produce fertile offspring. Species are identified by two names (binomial nomenclature). The first name is the genus, the second is the species.
For example, a lion is Panthera leo, a tiger is Panthera tigris. The first word is always capitalized, the second is not, and both should be italicized. Humans, of course, are Homo sapiens. The full classification for a lion would be: Kingdom, Animalia (animals); Phylum, Chordata (vertebrate animals); Class, Mammalia (mammals); Order, Carnivora (meat eaters); Family, Felidae (all cats); Genus, Panthera (great cats); Species, leo (lions).
noun, plural: kingdoms
In biology, kingdom is a taxonomic rank that is composed of smaller groups called phyla (or divisions, in plants).