exosphere vs layer

exosphere and layer both are nouns.

Word	Noun	Adjective	Verb	Adverb
exosphere	Yes	No	No	No
layer	Yes	No	Yes	No

As nouns, layer is a hypernym of exosphere; that is, layer is a word with a broader meaning than exosphere:

exosphere: the outermost atmospheric layer
layer: a relatively thin sheetlike expanse or region lying over or under another

exosphere (noun)	layer (noun)
the outermost atmospheric layer	thin structure composed of a single thickness of cells
	a hen that lays eggs
	single thickness of usually some homogeneous substance
	an abstract place usually conceived as having depth
	a relatively thin sheetlike expanse or region lying over or under another

exosphere (verb)	layer (verb)
	make or form a layer