clade

American  

[kleyd] / kleɪd /

noun

Biology.

1. a taxonomic group of organisms classified together on the basis of homologous features traced to a common ancestor.

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clade British  

/ kleɪd /

noun

1. biology a group of organisms considered as having evolved from a common ancestor

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clade Scientific  

/ klād /

1. A grouping of organisms made on the basis of their presumed evolutionary history, rather than purely on shared features. Clades consist of a common ancestor and all its descendants. The class Aves (birds) is a clade, but the class Reptilia (reptiles) is not, since it does not include birds, which are descended from the dinosaurs, a kind of reptile. Many modern taxonomists prefer to use clades in classification, and not all clades correspond to traditional groups like classes, orders, and phyla.

2. Compare grade

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Etymology

Origin of clade

First recorded in 1957, clade is from the Greek word kládos branch

Example Sentences

Since November 2024, there have been 12 reported cases of clade I monkeypox in the U.S., while clade II is “circulating at low levels,” per the Centers for Disease Control and Prevention.

From Barron's • Mar. 17, 2026

This also expands the known diversity of the European clade Rhabdodontia.

From Science Daily • Feb. 3, 2026

Although the vaccine hasn't been tested against clade Ib mpox, it is known to be effective in protecting against another strain called clade II.

From BBC • Oct. 27, 2025

Birds have been spreading a new clade of the H5N1 avian influenza virus, 2.3.4.4b, around the world since 2021.

From Science Magazine • Dec. 5, 2024

Lyrnessum Æacides, Ciconas vastavit Ulysses: Num facta est tali gloria clade minor?

From Gustavus Vasa and other poems by Walker, William Sidney