genus

genus, in taxonomy: see classification.

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genus

Biological classification. 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.

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genus

1. Biology any of the taxonomic groups into which a family is divided and which contains one or more species. For example, Vulpes (foxes) is a genus of the dog family (Canidae)

2. Logic a class of objects or individuals that can be divided into two or more groups or species

3. Maths a number characterizing a closed surface in topology equal to the number of handles added to a sphere to form the surface. A sphere has genus 0, a torus, genus 1, etc.

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genus [′jē·nəs]

(mathematics)

An integer associated to a surface which measures the number of holes in the surface.

(systematics)

A taxonomic category that includes groups of closely related species; the principal subdivision of a family.