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Any of various amoeboid protozoans having a hard external covering, found in soil and freshwater habitats.

[From New Latin Testācea, former order name, from Latin, neuter pl. of testāceus, covered with a shell, from testa, shell.]

tes·ta′cean adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Animals) any of various invertebrate animals with a hard shell
(Zoology) (of an invertebrate) having a hard shell
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.testacean - any of various rhizopods of the order Testacea characterized by having a shell
rhizopod, rhizopodan - protozoa characterized by a pseudopod
order Testacea, Testacea - testacean rhizopods
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
Aristotle is talking here about physis, the vital principle of plants or testaceans. A plant may need more water to stay alive than a testacean.
However, microfauna, for the most part, consist of the ciliated, flagellated, naked, and testacean protozoa.
The shell has three layers: cuticle or external, calcareous of intermediate and testacean of internal.