endoderm

noun

en·​do·​derm ˈen-də-ˌdərm 

1

a

: the innermost of the three primary germ layers of an embryo that is the source of the epithelium of the digestive tract and its derivatives and of the lower respiratory tract

b

: a tissue (such as esophageal or pancreatic tissue) derived from this germ layer

2

: the inner layer of cells of a diploblastic animal (such as a jellyfish or sponge)

endodermal

ˌen-də-ˈdər-məl 

adjective

Examples of endoderm in a Sentence

Recent Examples on the Web

Then, in the developing embryo, cells form three primary layers — ectoderm, mesoderm and endoderm — which, over time, become skin, neurons, heart, gut, and so on. —Viviane Callier, Quanta Magazine, 21 Mar. 2025

Its hollow shell is made of cells that will form the placenta (called trophoblast stem cells, or TSCs) and the yolk sac (the extra-embryonic endoderm, or XEN cells). —Philip Ball, Quanta Magazine, 13 June 2023

Word History

Etymology

French endoderme, from end- + Greek derma skin — more at derm-

First Known Use

1861, in the meaning defined at sense 2

Rhymes for endoderm

• disaffirm
• ectoderm
• endosperm
• interfirm
• isotherm
• mesoderm
• periderm
• reaffirm
• affirm
• bookworm
• confirm
• cutworm

Kids Definition

endoderm

noun

en·​do·​derm ˈen-də-ˌdərm 

1

: the innermost of the three basic layers of an embryo that forms the epithelium of the digestive tract and the parts of the body formed from it

2

: the inner layer of cells of an animal (as a jellyfish or hydra) whose body is composed of two layers of cells

endodermal

ˌen-də-ˈdər-məl 

adjective

Medical Definition

endoderm

noun

en·​do·​derm ˈen-də-ˌdərm 

: the innermost of the three primary germ layers of an embryo that is the source of the epithelium of the digestive tract and its derivatives and of the lower respiratory tract

also : a tissue that is derived from this germ layer

endodermal

ˌen-də-ˈdər-məl 

adjective