seborrhea vs skin disease

seborrhea and skin disease both are nouns.

Word	Noun	Adjective	Verb	Adverb
seborrhea	Yes	No	No	No
skin disease	Yes	No	No	No

As nouns, skin disease is a hypernym of seborrhea; that is, skin disease is a word with a broader meaning than seborrhea:

seborrhea: a condition in which overactivity of the sebaceous glands causes the skin to become oily
skin disease: a disease affecting the skin

Other hypernyms of seborrhea include disease of the skin, skin disorder.

seborrhea (noun)	skin disease (noun)
a condition in which overactivity of the sebaceous glands causes the skin to become oily	a disease affecting the skin