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echinoderm

[ ih-kahy-nuh-durm, ek-uh-nuh- ]
/ ɪˈkaɪ nəˌdɜrm, ˈɛk ə nə- /
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noun

any marine animal of the invertebrate phylum Echinodermata, having a radiating arrangement of parts and a body wall stiffened by calcareous pieces that may protrude as spines and including the starfishes, sea urchins, sea cucumbers, etc.

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Origin of echinoderm

1825–35; taken as singular of New Latin Echinodermata, neuter plural of echinodermatus<Greek echîn(os) sea urchin + -o--o- + -dermatos-dermatous

Words nearby echinoderm

echinate, echino-, echinococcosis, echinococcus, echinococcus cyst, echinoderm, echinodermatous, echinoid, echinulate, echinus, echium
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

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British Dictionary definitions for echinoderm

echinoderm
/ (ɪˈkaɪnəʊˌdɜːm) /

noun

any of the marine invertebrate animals constituting the phylum Echinodermata, characterized by tube feet, a calcite body-covering (test), and a five-part symmetrical body. The group includes the starfish, sea urchins, and sea cucumbers

Derived forms of echinoderm

echinodermal or echinodermatous, adjective
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

Scientific definitions for echinoderm

echinoderm
[ ĭ-kī′nə-dûrm′ ]

Any of various marine invertebrates of the phylum Echinodermata, having a latticelike internal skeleton composed of calcite and usually a hard, spiny outer covering. The body plans of adult echinoderms show radial symmetry, typically in the pattern of a five-pointed star, while the larvae show bilateral symmetry. Echinoderms probably share a common ancestor with the hemichordates and chordates, and were already quite diversified by the Cambrian Era. They include the starfish, sea urchins, sand dollars, holothurians (sea cucumbers), and crinoids, as well as thousands of extinct forms.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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