cradle cap vs dermatitis

cradle cap and dermatitis both are nouns.

Word	Noun	Adjective	Verb	Adverb
cradle cap	Yes	No	No	No
dermatitis	Yes	No	No	No

As nouns, dermatitis is a hypernym of cradle cap; that is, dermatitis is a word with a broader meaning than cradle cap:

cradle cap: a dermatitis of the scalp that is common in infants
dermatitis: inflammation of the skin; skin becomes itchy and may develop blisters

cradle cap (noun)	dermatitis (noun)
a dermatitis of the scalp that is common in infants	inflammation of the skin; skin becomes itchy and may develop blisters