dysplasia vs hypoplasia

dysplasia and hypoplasia both are nouns.

Word	Noun	Adjective	Verb	Adverb
dysplasia	Yes	No	No	No
hypoplasia	Yes	No	No	No

As nouns, hypoplasia is a hyponym of dysplasia; that is, hypoplasia is a word with a more specific, narrower meaning than dysplasia:

dysplasia: abnormal development (of organs or cells) or an abnormal structure resulting from such growth
hypoplasia: underdevelopment of an organ because of a decrease in the number of cells

Other hyponyms of dysplasia include aplasia, fibrous dysplasia of bone, hypertrophy, hyperplasia, anaplasia.

dysplasia (noun)	hypoplasia (noun)
abnormal development (of organs or cells) or an abnormal structure resulting from such growth	underdevelopment of an organ because of a decrease in the number of cells