The systematic practice of discriminating against and segregating Black people, especially as practiced in the American South from the end of Reconstruction to the mid-20th century.
adjective
Upholding or practicing discrimination against and segregation of Black people: Jim Crow laws; a Jim Crow town.
Reserved or set aside for a racial or ethnic group that is to be discriminated against: “I told them I wouldn't take a Jim Crow job”(Ralph Bunche).