What is bonk in American slang?

I'm curious, what exactly is meant by the term "bonk" in American slang? I've heard it used in a few conversations, but I'm not quite sure of its exact definition. Is it a playful or humorous term, or does it have a more serious connotation? I'd appreciate it if you could provide a clear and concise explanation of this term, as well as any relevant context or examples where it might be used.