It's literal definition is "Humble Skin" or "Humble Color"
Mainly used by the latinos, it is used by another latino to refer to another latino.
Used also as a discriminatory term to refer to Peruvians, Bolivians, lower-class Mexicans, etc, etc.
(altough many of us dont mind)
person 1: Soy color humilde, maldita sea.
person 2: Jaja que pendejo.
person 2: Somos del mismo color idiota!