anarthria vs defect of speech

anarthria and defect of speech both are nouns.

Word	Noun	Adjective	Verb	Adverb
anarthria	Yes	No	No	No
defect of speech	Yes	No	No	No

As nouns, defect of speech is a hypernym of anarthria; that is, defect of speech is a word with a broader meaning than anarthria:

anarthria: partial or total loss of articulate speech resulting from lesions of the central nervous system
defect of speech: a disorder of oral speech

Other hypernyms of anarthria include speech defect, speech disorder.

anarthria (noun)	defect of speech (noun)
partial or total loss of articulate speech resulting from lesions of the central nervous system	a disorder of oral speech