genus

American  

[jee-nuhs] / ˈdʒi nəs /

noun

• genera,
  plural
• genuses
  plural

1. Biology. the usual major subdivision of a family or subfamily in the classification of organisms, usually consisting of more than one species.

2. Logic. a class or group of individuals, or of species of individuals.

3. a kind; sort; class.

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genus British  

/ ˈdʒiːnəs /

noun

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. a class, group, etc, with common characteristics

4. 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 Scientific  

/ jē′nəs /

• genera
  plural

1. 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.”

2. See Table at taxonomy

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genus Cultural  

1. In biology, the classification lower than a family and higher than a species. Wolves belong to the same genus as dogs. Foxes belong to a different genus from that of dogs and wolves, but to the same family. (See Linnean classification.)

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Other Word Forms

Derived Forms

• pseudogenus
  noun

Inflected Forms

Nouns

• genera
  plural
• genuses
  plural

Etymology

Origin of genus

1545–55; < Latin: race, stock, kind, gender; cognate with Greek génos. See gens, gender ¹, kin

Explanation

A genus is a class or group of something. In biology, it's a taxonomic group covering more than one species. This is a term used by biologists to classify more than one species under a larger umbrella. In biology, the word family describes the broadest group category, then genus, and then species. For example, primates are a family, and humans are a species within that family, but we're not in the same genus as macaques: macaques have their own genus. Dogs and wolves are so closely related they’re in the same genus. The plural of genus is genera.

Example Sentences

See Examples For:

genus genera genuses

Although scientists have long known how CAM works, exactly how it evolved within the genus Clusia, and why different species use it in different ways, has remained unclear.

From Science Daily ● Sep. 23, 2026

Homo erectus, or H.erectus, occupies an important place in human evolutionary history because it was the first species in the genus Homo known to have migrated out of Africa.

From Science Daily ● Sep. 10, 2026

The plant was growing at an elevation of nearly 1,000 meters, an unusually high and seasonally dry environment for members of the genus.

From Science Daily ● Sep. 4, 2026

The chance to name a species produces a curious sort of immortality for the bestowers: Their names might forever be attached to the animals, right after the genus and species.

From The Wall Street Journal ● Aug. 28, 2026

Humans first evolved in East Africa about 2.5 million years ago from an earlier genus of apes called Australopithecus, which means ‘Southern Ape’.

From "Sapiens: A Brief History of Humankind" by Yuval Noah Harari

Dr Matthew McCurry, Curator of Palaeontology, Australian Museum, said the discovery of three new genera of monotremes helps to piece together their remarkable evolutionary story.

From Science Daily ● May 27, 2024

In the end, the team used data from about 60 percent of all modern genera of plants.

From New York Times ● May 11, 2024

Using this method, the team sequenced part of the nuclear genomes from about 8000 genera of angiosperms—about 60% of all flowering plants on Earth—and compared 353 of their genes.

From Science Magazine ● Apr. 23, 2024

This has likely kept gar genomes so stable that species and even genera whose last common ancestor lived more than 100 million years ago have diverged very little.

From Science Magazine ● Mar. 8, 2024

According to current estimates, within that short interval, North America lost thirty-four out of its forty-seven genera of large mammals.

From "Sapiens: A Brief History of Humankind" by Yuval Noah Harari

Almost 300 biologists have banded together and redrawn the tree of life for flowering plants, enabling a 15-fold increase in the number of genuses represented and highlighting new milestones in diversification.

From Science Magazine ● Apr. 24, 2024

There are more than 100 species of Nepenthes, which is one of the many genuses of carnivorous plants found around the world.

From New York Times ● May 18, 2022

This uncanny deadliness has a mystery at its core: These mushrooms are from three separate genuses, or groups of fungal species, that are not closely related.

From New York Times ● May 9, 2022

Anemone and Aster are large genuses in their own right, filled with poppy- and daisy-like blooms.

From Slate ● May 17, 2016

Genus, a sort, becomes genera in Latin, and genuses in English.

From The Grammar of English Grammars by Goold Brown