echinoderm
[ ih-kahy-nuh-durm, ek-uh-nuh- ]
/ ɪˈkaɪ nəˌdɜrm, ˈɛk ə nə- /
Save This Word!
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.
QUIZZES
QUIZ YOURSELF ON "WAS" VS. "WERE"!
Were you ready for a quiz on this topic? Well, here it is! See how well you can differentiate between the uses of "was" vs. "were" in this quiz.
Question 1 of 7
“Was” is used for the indicative past tense of “to be,” and “were” is only used for the subjunctive past tense.
Meet Grammar Coach
Improve Your Writing
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
Example sentences from the Web for echinoderm
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, adjectiveCollins 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.