A term used to classify the act of hating a particular group of people because of skin color, origin, or religion. You should hate people for who they are, not what they look like or believe in. Only ignorant people are racist, and when asked "Why?" they tend to studder and generally look stupid.
Racist person: "I hate (insert race, group, religion, etc. here)!"
Racist person: "Erm...uh...hm..."