radial symmetry

American  

noun

Biology.

1. a basic body plan in which the organism can be divided into similar halves by passing a plane at any angle along a central axis, characteristic of sessile and bottom-dwelling animals, as the sea anemone and starfish.

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radial symmetry British  

noun

1. a type of structure of an organism or part of an organism in which a vertical cut through the axis in any of two or more planes produces two halves that are mirror images of each other Compare bilateral symmetry

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radial symmetry Scientific  

1. Symmetrical arrangement of parts of an organism around a single main axis, so that the organism can be divided into similar halves by any plane that contains the main axis. The body plans of echinoderms, ctenophores, cnidarians, and many sponges and sea anemones show radial symmetry.

2. Compare bilateral symmetry

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Etymology

Origin of radial symmetry

First recorded in 1885–90

Compare meaning

How does radial-symmetry compare to similar and commonly confused words? Explore the most common comparisons:

• radial symmetry vs. bilateral symmetry

Example Sentences

But starfish—as well as sand dollars and sea anemones—have radial symmetry, with identical segments of their body radiating out from a central point.

From Scientific American • Nov. 3, 2023

A set of molecular markers on a sea star’s genes determine the animal’s body plan, which includes its radial symmetry and organ structure.

From Scientific American • Nov. 3, 2023

The end result, constructed at Harvard, resembled the nave of a cathedral built by aliens to worship radial symmetry, or an iron maiden for punishing giant cubes.

From New York Times • Nov. 23, 2022

What is radial symmetry and why is it advantageous to certain aquatic organisms?

From Textbooks • Jun. 9, 2022

They have few or rudimentary arms and short stalks, and want the beautiful radial symmetry of the typical star-fishes.

From The Chain of Life in Geological Time A Sketch of the Origin and Succession of Animals and Plants by Dawson, Sir J. William