atypicality vs abnormalcy

atypicality and abnormalcy both are nouns.

Word	Noun	Adjective	Verb	Adverb
atypicality	Yes	No	No	No
abnormalcy	Yes	No	No	No

As nouns, abnormalcy is a hypernym of atypicality; that is, abnormalcy is a word with a broader meaning than atypicality:

atypicality: any state that is not typical
abnormalcy: an abnormal physical condition resulting from defective genes or developmental deficiencies

Other hypernyms of atypicality include abnormality.

atypicality (noun)	abnormalcy (noun)
any state that is not typical	an abnormal physical condition resulting from defective genes or developmental deficiencies