vitiligo vs skin disorder

vitiligo and skin disorder both are nouns.

Word	Noun	Adjective	Verb	Adverb
vitiligo	Yes	No	No	No
skin disorder	Yes	No	No	No

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

vitiligo: an acquired skin disease characterized by patches of unpigmented skin (often surrounded by a heavily pigmented border)
skin disorder: a disease affecting the skin

Other hypernyms of vitiligo include disease of the skin, skin disease.

vitiligo (noun)	skin disorder (noun)
an acquired skin disease characterized by patches of unpigmented skin (often surrounded by a heavily pigmented border)	a disease affecting the skin