germ layer vs ectoderm

germ layer and ectoderm both are nouns.

Word	Noun	Adjective	Verb	Adverb
germ layer	Yes	No	No	No
ectoderm	Yes	No	No	No

As nouns, ectoderm is a hyponym of germ layer; that is, ectoderm is a word with a more specific, narrower meaning than germ layer:

germ layer: (embryology) any of the 3 layers of cells differentiated in embryos following gastrulation
ectoderm: the outer germ layer that develops into skin and nervous tissue

Other hyponyms of germ layer include ectoblast, exoderm, mesoblast, mesoderm, endoblast, endoderm, entoblast, entoderm, hypoblast.

germ layer (noun)	ectoderm (noun)
(embryology) any of the 3 layers of cells differentiated in embryos following gastrulation	the outer germ layer that develops into skin and nervous tissue