In slang, "dust" can have a few different meanings depending on the context. Here are some possibilities:

1. Cocaine: "Dust" is sometimes used as a slang term for cocaine, particularly in the hip-hop community.

2. Old or worn-out: If someone says something is "dusty," they might mean that it's old or worn-out. For example, if someone is wearing outdated fashion, they might be referred to as "dusty."

3. To leave quickly: "Dusting" can mean leaving or departing quickly. For example, if someone says "I'm gonna dust," they mean they're going to leave soon.

4. To defeat easily: If someone "dusts" their opponent, it means they easily defeated them in a competition or argument.

It's worth noting that the meaning of slang terms can vary depending on the region and context in which they are used.