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

Jones said the best way to spot healthy peatland was the plants growing on it, "there'll be grasses, sedges, heathers, critically there will often be bog mosses of the genus sphagnum".

From BBC ● Jul. 3, 2026

The spider, which belongs to the genus Propostira, was initially observed by biomedical researcher Greg Anderson - also a spider researcher and photographer.

From BBC ● Jun. 23, 2026

Comparisons with the modern ant genus Liometopum, which is found today in North America and warmer parts of Europe, offer clues about how the extinct species may have lived.

From Science Daily ● Jun. 4, 2026

The site has produced the oldest known member of the genus Homo and the earliest known Oldowan stone tools on Earth.

From Science Daily ● May 16, 2026

Being a human belonging to the wallflower genus, I’m kinda used to swallowing my words instead of speaking them.

From "From Twinkle, with Love" by Sandhya Menon

Since the behavioral data did not always align perfectly with the species in that phylogeny, the researchers simplified the evolutionary tree to 44 genera, along with five families and one superfamily.

From Science Daily ● May 2, 2026

In fact, more than 10,000 species have been described in just 83 big genera since the year 2000, which is about 2.5 times the size of the total flora of Ireland.

From Science Daily ● May 29, 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

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

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

From Slate ● May 17, 2016

Paleontologists have documented five new genuses of dinosaurs and six previously unknown species since research began in the 1980s in partnership with French scientists.

From New York Times ● Jul. 13, 2010

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

From The Grammar of English Grammars by Brown, Goold