schistorrhachis vs birth defect

schistorrhachis and birth defect both are nouns.

Word	Noun	Adjective	Verb	Adverb
schistorrhachis	Yes	No	No	No
birth defect	Yes	No	No	No

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

schistorrhachis: a not uncommon congenital defect in which a vertebra is malformed; unless several vertebrae are affected or there is myelomeningocele there are few symptoms; can be diagnosed by amniocentesis
birth defect: a defect that is present at birth

Other hypernyms of schistorrhachis include congenital abnormality, congenital anomaly, congenital defect, congenital disorder.

schistorrhachis (noun)	birth defect (noun)
a not uncommon congenital defect in which a vertebra is malformed; unless several vertebrae are affected or there is myelomeningocele there are few symptoms; can be diagnosed by amniocentesis	a defect that is present at birth