Reino

Reino is the Spanish and Portuguese term for "kingdom." In biology, it denotes a major taxonomic rank used to group organisms at a high level; the name comes from Latin regnum. The concept is used in both scientific and educational contexts.

Historically, the five-kingdom model, proposed by Whittaker in 1969, divided life into Monera, Protista, Fungi, Plantae, and Animalia. This framework emphasized differences in cellular organization and nutrition. Since the late 20th century, many biologists use the three-domain system (Bacteria, Archaea, Eukarya). Within Eukarya, varying classifications apply kingdoms such as Animalia, Plantae, and Fungi, while some lineages are placed in Protista or in other higher-rank groups; prokaryotes are typically organized at the domain level. Thus the use of "reino" as a formal rank is more common in educational settings and certain traditional classifications than in some modern phylogenetic systems.

In broader usage, reino also means a political realm ruled by a king, or religious contexts like "el reino de Dios" (the kingdom of God).

Etymology: from Latin regnum, related to regere, to rule.