碰杯 (pèng bēi) literally means 'to bump cups' — the character 碰 (pèng) means 'to touch, bump, or collide', and 杯 (bēi) means 'cup' or 'glass'. Together, they form a verb describing the celebratory gesture of lightly tapping glasses together before drinking, especially during toasts at meals, parties, weddings, or business dinners. It’s a deeply rooted social custom in Chinese culture, symbolizing goodwill, unity, and shared joy.

This action is almost always performed with alcohol (like baijiu, beer, or wine), though non-alcoholic drinks may also be used. The phrase implies intentionality and politeness: participants usually make eye contact, smile, say a short toast (e.g., 干杯 gān bēi — 'bottoms up!'), and then gently clink rims or sides of their glasses. While not strictly formal, it’s considered impolite to skip 碰杯 when others initiate it in group settings.