astomatal vs stoma

astomatal is not a noun while stoma is a noun.

Word	Noun	Adjective	Verb	Adverb
astomatal	No	Yes	No	No
stoma	Yes	No	No	No

astomatal (noun)	stoma (noun)
	a mouth or mouthlike opening (especially one created by surgery on the surface of the body to create an opening to an internal organ)
	a minute epidermal pore in a leaf or stem through which gases and water vapor can pass

astomatal (adjective)	stoma (adjective)
lacking a stoma or stomata