mammy

noun

1. (childish)mamma; mother
2. (US, derogatory, historical, often)In the southern United States, a black nanny employed to look after white children; or in the antebellum South, a female slave who was close to the household and looked after the children.

   “That's what you for—to help white folks keep niggers down. That's why he sent you to me. They be calling you mammy in a few years. You be running the whole house when the old man dies.”