What is 'sjb' mean in Chinese Slang?

This one’s a bit harsh but often used jokingly. The letters "sjb" stand for "神经病" (shén jīng bìng), which literally means "mental illness" but is commonly used to call someone a "psycho" or "crazy" in a teasing way. It’s not meant to be taken seriously among friends.

Example: If your friend does something wild, you might laugh and say, "You’re such an sjb!"

Fun fact: It’s often used in a lighthearted way, but be careful—it can sound rude if used with someone you’re not close to.