Meaning of GENUS in English
It ranks below family and above species, consisting of structurally or phylogenetically (see phylogenetic tree) related species or a single species exhibiting unusual differences. For example, the species of roses collectively form the genus Rosa and those of horses, donkeys, and zebras form the genus Equus . The genus name, capitalized and usually italicized, is the first word of a scientific name in the system of binomial nomenclature .
Britannica Concise Encyclopedia. Краткая энциклопедия Британика. 2012