When the make up applied to a person's face is so powerful and amazing that it makes them look truly stunning. 'Beat' can also be used to describe any variety of things, not just one's face. The term is popular among make up enthusiasts and the gay community.
1. Did you see Angela at her wedding? Her face was beat for a whole new year
2. I'm about to give you beat face, darling.
3. Tommy's outfit is beat. He's about to go party.