kaffir - A word that means you're not religious, and in South Africa,

A word that means you're not religious, and in South Africa, it's used to insult black people like they're the worst kind of loser.

My teacher called me a kaffir for not knowing how to write.

My friend got called a kaffir for not knowing how to add.

My brother screamed 'Kaffir!' because I spilled soup on his shirt.