genus
Americannoun
plural
genera, genuses-
Biology. the usual major subdivision of a family or subfamily in the classification of organisms, usually consisting of more than one species.
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Logic. a class or group of individuals, or of species of individuals.
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a kind; sort; class.
noun
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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 )
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logic a class of objects or individuals that can be divided into two or more groups or species
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a class, group, etc, with common characteristics
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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
plural
genera-
A group of organisms ranking above a species and below a family. The names of genera, like those of species, are written in italics. For example, Periplaneta is the genus of the American cockroach, and comes from the Greek for “wandering about.”
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See Table at taxonomy
Other Word Forms
- pseudogenus noun
Etymology
Origin of genus
1545–55; < Latin: race, stock, kind, gender; cognate with Greek génos. See gens, gender 1, kin
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
The insects belong to the genus Batracomorphus, a group of leafhoppers.
From Science Daily • Mar. 11, 2026
Genetic analysis confirmed that the organism represents not only a newly identified species but also an entirely new genus.
From Science Daily • Mar. 6, 2026
However, this marks the first new genus of Early Jurassic ichthyosaur described from the region in more than 100 years.
From Science Daily • Feb. 24, 2026
While some members of this genus can cause infections in people or animals, they are also considered promising for biotechnology applications.
From Science Daily • Feb. 21, 2026
Both houseflies and mosquitoes of the genus Culex began to show resistance to the sprays.
From "Silent Spring" by Rachel Carson
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.