[ ek-tuh-durm ]
/ ˈɛk təˌdɜrm /
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noun Embryology.

the outer germ layer in the embryo of a metazoan.



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Also called ectoblast.

Origin of ectoderm

First recorded in 1860–65; ecto- + -derm
ec·to·der·mal, ec·to·der·mic, adjectiveec·to·der·moi·dal [ek-toh-der-moid-l], /ˌɛk toʊ dərˈmɔɪd l/, adjectivesub·ec·to·der·mal, adjectivesub·ec·to·der·mic, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

British Dictionary definitions for ectoderm



/ (ˈɛktəʊˌdɜːm) /


the outer germ layer of an animal embryo, which gives rise to epidermis and nervous tissueSee also mesoderm, endoderm
ectodermal or ectodermic, 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

Medical definitions for ectoderm

[ ĕktə-dûrm′ ]


The outermost of the three primary germ layers of an embryo, from which the epidermis, nervous tissue, and sense organs develop.ectoblast
ec′to•dermal null adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for ectoderm

[ ĕktə-dûrm′ ]

The outermost of the primary germ layers of an animal embryo. In vertebrates, the ectoderm gives rise to the epidermis and associated tissues (such as hair and sweat glands), enamel of the teeth, sense organs, nervous system, and lining of the nose, mouth, and anus. Compare endoderm mesoderm.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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