atonicity vs atonia

atonicity and atonia both are nouns.

Word	Noun	Adjective	Verb	Adverb
atonicity	Yes	No	No	No
atonia	Yes	No	No	No

As nouns, atonicity and atonia are synonyms defined as:

Other synonyms of atonicity include amyotonia, atony.

atonicity (noun)	atonia (noun)
lack of normal muscular tension or tonus	lack of normal muscular tension or tonus