ectoderm

American  

[ek-tuh-durm] / ˈɛk təˌdɜrm /

noun

Embryology.

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

---

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

---

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

---

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

See Examples For:

ectoderm

During normal embryonic development, they give rise to three major cell types: endoderm, ectoderm, and mesoderm.

From Science Daily ● Aug. 28, 2026

If an embryo failed to form ectoderm, the nervous system would not develop, she said.

From Science Daily ● Aug. 28, 2026

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

Moreover, the developmental pathway through surface ectoderm state to amniotic ectoderm state was also observed in primate embryos.

From Science Daily ● Mar. 4, 2024

The shading is due to an increased growth of cells, because here the three germinal layers—embryonic ectoderm, mesoderm, and entoderm—are in contact.

From Embryology The Beginnings of Life by Gerald R. Leighton

Related Words

• fur
• leather
• skin
• wool