alveolar arch vs outgrowth

alveolar arch and outgrowth both are nouns.

Word	Noun	Adjective	Verb	Adverb
alveolar arch	Yes	No	No	No
outgrowth	Yes	No	No	No

As nouns, outgrowth is a hypernym of alveolar arch; that is, outgrowth is a word with a broader meaning than alveolar arch:

alveolar arch: the part of the upper or lower jawbones in which the teeth are set
outgrowth: a natural prolongation or projection from a part of an organism either animal or plant

Other hypernyms of alveolar arch include appendage, process.

alveolar arch (noun)	outgrowth (noun)
the part of the upper or lower jawbones in which the teeth are set	a natural prolongation or projection from a part of an organism either animal or plant
	the gradual beginning or coming forth
	a natural consequence of development