meta·​zo·​an ˌme-tə-ˈzō-ən How to pronounce metazoan (audio)
: any of a group (Metazoa) that comprises all animals having the body composed of cells differentiated into tissues and organs and usually a digestive cavity lined with specialized cells
metazoan adjective

Examples of metazoan in a Sentence

Recent Examples on the Web This is just one of the myriad reasons biologists give for the long term lack of success of parthenogenetic metazoan lineages. Razib Khan, Discover Magazine, 22 July 2013 The same drama is played out among the cells that make up every metazoan since the Cambrian Explosion, when multicellular life began. George Johnson, Discover Magazine, 7 Sep. 2013 Meanwhile, Knauth theorizes, oxygen-utilizing metazoans could have evolved on moist mats of oxygen producers kept hydrated by rains, lakes, streams and rivers during the late Precambrian. Peter Byrne, Quanta Magazine, 24 Apr. 2014

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'metazoan.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


New Latin Metazoa, from meta- + -zoa

First Known Use

1879, in the meaning defined above

Time Traveler
The first known use of metazoan was in 1879

Dictionary Entries Near metazoan

Cite this Entry

“Metazoan.” Dictionary, Merriam-Webster, Accessed 29 Nov. 2023.

Kids Definition


meta·​zo·​an ˌmet-ə-ˈzō-ən How to pronounce metazoan (audio)
: any of the great group of animals with a body composed of cells forming tissues and organs
metazoan adjective

Medical Definition


meta·​zo·​an -ˈzō-ən How to pronounce metazoan (audio)
: any of the animals that comprise the taxon Metazoa, that have the body when adult composed of numerous cells differentiated into tissues and organs and usually a digestive cavity lined with specialized cells, and that usually include the coelenterates and all higher animals but sometimes also include the sponges and mesozoans
metazoan adjective
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