Bruh

Slang for

"Are you serious?" or "Are you kidding me?" OR "Are you for real?"

Bruh, why the heck did you do that?

Onomatopoeia

How am I supposed to know what this means? This is Urban Dictionary, not Dictionary.com. You've lost a few brain cells over the week if you're really here looking for this word.

Who would even use this word in a sentence? Onomatopoeia means... I honestly don't even know.