What is '213' mean in Chinese Slang?

This one’s a bit cheeky. The numbers 2-1-3 sound like "èr bī" (二逼) in Chinese, which is a slang term for someone who’s acting stupid or clueless. It’s not super harsh, but it’s definitely playful and teasing. Use it with friends when they do something silly.

Example: If your friend forgets their keys, you might joke, "Haha, 213!"

Fun fact: It’s often used in gaming or online forums to poke fun at someone’s mistakes.