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.
Compare bilateral symmetry.
Origin of radial symmetry
First recorded in 1885–90
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
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 otherCompare bilateral symmetry
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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. Compare bilateral symmetry.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.