pallor vs skin color

pallor and skin color both are nouns.

Word	Noun	Adjective	Verb	Adverb
pallor	Yes	No	No	No
skin color	Yes	No	No	No

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

pallor: unnatural lack of color in the skin (as from bruising or sickness or emotional distress)
skin color: the coloring of a person's face

Other hypernyms of pallor include complexion, skin colour.

pallor (noun)	skin color (noun)
unnatural lack of color in the skin (as from bruising or sickness or emotional distress)	the coloring of a person's face