alveolar vs alveolus

alveolar and alveolus both are nouns.

Word	Noun	Adjective	Verb	Adverb
alveolar	Yes	Yes	No	No
alveolus	Yes	No	No	No

alveolar (noun)	alveolus (noun)
a consonant articulated with the tip of the tongue near the gum ridge	a tiny sac for holding air in the lungs; formed by the terminal dilation of tiny air passageways
	a bony socket in the alveolar ridge that holds a tooth

alveolar (adjective)	alveolus (adjective)
pertaining to the tiny air sacs of the lungs
pertaining to the sockets of the teeth or that part of the upper jaw