Genus

noun

(L. genus, race) (pl. genera) A group of closely related species; the taxonomic category ranking above a species and below a family; a class, kind, or group marked by common characteristics or by one common characteristic; specifically a category of biological classification ranking between the family and the species, comprising structurally or phylogenetically related species or an isolated species exhibiting unusual differentiation, and being designated by a Latin or latinized capitalized singular noun. Distinctions between genera are sometimes empirical or arbitrary and liable to modification as knowledge advances. A category antedating binomial nomenclature, composed of plants with two or three characters of reproductive structures in common, although characters used for separation vary widely among different families.