humpback vs spinal curvature

humpback and spinal curvature both are nouns.

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

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

humpback (noun)	spinal curvature (noun)
large whalebone whale with long flippers noted for arching or humping its back as it dives	an abnormal curvature of the vertebral column
a person whose back is hunched because of abnormal curvature of the upper spine
an abnormal backward curve to the vertebral column