In biological classification, taxonomic rank is the relative level of a group of organisms (a taxon) in a taxonomic hierarchy.

A given rank subsumes under it less general categories, that is, more specific descriptions of life forms. Above it, each rank is classified within more general categories of organisms and groups of organisms related to each other through inheritance of traits or features from common ancestors. The rank of any species and the description of its genus is basic; which means that to identify a particular organism, it is usually not necessary to specify ranks other than these first two.

There are seven main taxonomic ranks: kingdom, phylum or division, class, order, family, genus, species.

Family (Latin: familia, plural familiae) is one of the eight major taxonomic ranks; it is classified between order and genus. A family may be divided into subfamilies, which are intermediate ranks above the rank of genus. In vernacular usage, a family may be named after one of its common members; for example, walnuts and hickory trees belong to the family Juglandaceae, commonly known as the walnut family.

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