bi·​la·​te·​ri·​an | \ ˌbī-lə-ˈtir-ē-ən How to pronounce bilaterian (audio) \
plural bilaterians

Definition of bilaterian

: an animal having bilateral symmetry Scientists refer to animals, including humans, with this two-sided symmetry as bilaterians.— Carl Zimmer, New York Times, 21 June 2005 Comb jellies and cnidarians branched off before bilaterians diversified into the variety of animal groups known today, and they are considered relatively “simple” organisms.— Elizabeth Pennisi, Science, 6 July 2007

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Other Words from bilaterian

bilaterian adjective
bilaterian animals … it is possible that bilaterian life emerged early in the Ediacaran, but at present, no fossils or trace fossils from this time have been reported. — Ernesto Pecoits et al., Science, 29 June 2012

First Known Use of bilaterian

1983, in the meaning defined above

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The first known use of bilaterian was in 1983

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Cite this Entry

“Bilaterian.” The Dictionary, Merriam-Webster Inc., Accessed 24 January 2020.

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a feeling of well-being or elation

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