spinal curvature vs abnormalcy

spinal curvature and abnormalcy both are nouns.

Word	Noun	Adjective	Verb	Adverb
spinal curvature	Yes	No	No	No
abnormalcy	Yes	No	No	No

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

spinal curvature: an abnormal curvature of the vertebral column
abnormalcy: an abnormal physical condition resulting from defective genes or developmental deficiencies

Other hypernyms of spinal curvature include abnormality.

spinal curvature (noun)	abnormalcy (noun)
an abnormal curvature of the vertebral column	an abnormal physical condition resulting from defective genes or developmental deficiencies