bilateral symmetry

noun

: symmetry in which similar anatomical parts are arranged on opposite sides of a median axis so that only one plane can divide the individual into essentially identical halves

Examples of bilateral symmetry in a Sentence

Recent Examples on the Web Unlike bilaterians such as salamanders (and humans), which have bilateral symmetry (meaning a symmetrical right and left side), cnidarians have radial body symmetry, with body sections that extend out from the middle and are symmetrical all around. Elizabeth Rayne, Ars Technica, 3 Jan. 2024 Yet, oddly, sea stars start their lives as larvae with bilateral symmetry, before changing into their radial adult form. Margaret Osborne, Smithsonian Magazine, 6 Nov. 2023 Humans and most other animals, on the other hand, have bilateral symmetry—meaning we can be separated down the middle into two equal parts. Margaret Osborne, Smithsonian Magazine, 6 Nov. 2023 Looking at the wide swath of animal life represented by sponges, cnidarians (such as hydras, jellyfish and corals) and bilaterians (animals with bilateral symmetry), the researchers found 29 blocks of genes that were highly conserved among their chromosomes. Quanta Magazine, 2 Feb. 2022 These three challenges revealed that starfish have a hidden bilateral symmetry, and move in a preferred direction. Ed Yong, Discover Magazine, 17 Jan. 2012 Frontal view of the compound eye showing its bilateral symmetry. Christie Wilcox, Discover Magazine, 8 Jan. 2014 Ji and Wu think that this hint of bilateral symmetry is a faint vestige of the body that starfish have as larvae. Ed Yong, Discover Magazine, 17 Jan. 2012 Related Articles Dakota beadwork often uses the concept of bilateral symmetry — the children’s coat’s left and right lapels are completely identical. Liv Martin, Twin Cities, 1 Dec. 2019

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

Word History

First Known Use

1828, in the meaning defined above

Time Traveler
The first known use of bilateral symmetry was in 1828

Dictionary Entries Near bilateral symmetry

Cite this Entry

“Bilateral symmetry.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/bilateral%20symmetry. Accessed 14 Apr. 2024.

Kids Definition

bilateral symmetry

noun
: plant and animal symmetry in which similar parts are arranged so that one and only one plane can divide the individual into identical or nearly identical halves compare radial symmetry

Medical Definition

bilateral symmetry

noun
: symmetry in which similar anatomical parts are arranged on opposite sides of a median axis so that one and only one plane can divide the individual into essentially identical halves

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