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 researchers named the genus Algophthora by combining the word 'alga' with the Greek word 'phthora', meaning 'destruction'.
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
The public naming campaign began after Ze Frank featured the rare deep-sea chiton from the genus Ferreiraella in an episode of his "True Facts" YouTube series.
From Science Daily • Feb. 7, 2026
"This discovery is so much more than a simple snapshot of Paranthropus' occurrence: It sheds fresh light on the driving forces behind the evolution of the genus."
From Science Daily • Jan. 23, 2026
Biologists label organisms with a two-part Latin name, genus followed by species.
From "Sapiens: A Brief History of Humankind" by Yuval Noah Harari
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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.