ectoderm

American  

[ek-tuh-durm] / ˈɛk təˌdɜrm /

noun

Embryology.

1. the outer germ layer in the embryo of a metazoan.

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ectoderm British  

/ ˈɛktəʊˌdɜːm /

noun

1. the outer germ layer of an animal embryo, which gives rise to epidermis and nervous tissue See also mesoderm endoderm

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ectoderm Scientific  

/ ĕk′tə-dûrm′ /

1. 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.

2. Compare endoderm mesoderm

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Other Word Forms

• ectodermal
  adjective
• ectodermic
  adjective
• ectodermoidal
  adjective
• subectodermal
  adjective
• subectodermic
  adjective

Etymology

Origin of ectoderm

First recorded in 1860–65; ecto- + -derm

Example Sentences

Because both the brain and skin develop from the same embryonic layer called the ectoderm, the scientists set out to explore how these two systems might be connected.

From Science Daily • Oct. 13, 2025

Amniotic and surface ectoderm cells are specialised at an early stage of development and largely share biological features, such as gene expression patterns and signal requirements.

From Science Daily • Mar. 4, 2024

Dr Nakanoh customised culture conditions for hPSCs and found that the supplements Activin A, BMP4, a GSK3-beta inhibitor, and a MEK inhibitor promoted their differentiation into amniotic ectoderm.

From Science Daily • Mar. 4, 2024

Diploblasts have a non-living layer between the endoderm and ectoderm.

From Textbooks • Jan. 1, 2015

Amongst other structures which arise from the important layer of ectoderm are the teeth.

From Embryology The Beginnings of Life by Leighton, Gerald R.

Related Words

• fur
• leather
• skin
• wool