穿帮 (chuān bāng) literally means 'the cover is pierced' — 穿 (chuān) means 'to pierce, penetrate, or break through', and 帮 (bāng) here is an old colloquial term for 'cover', 'facade', or 'pretense' (not to be confused with the common word 帮 meaning 'to help'). Together, the phrase vividly conveys the moment when a deception, lie, or pretense is unintentionally exposed — like a mask slipping or a hidden truth leaking out. It's often used in informal speech to describe situations where someone’s false claim, fake identity, or staged performance fails unexpectedly.

This expression is commonly heard in daily conversation, entertainment commentary (e.g., criticizing an actor’s unconvincing disguise), or light-hearted teasing among friends. While it carries a mildly negative or humorous tone, it rarely implies serious wrongdoing — more often, it highlights awkwardness or carelessness. The verb typically appears in perfective aspect (e.g., 穿帮了) or as part of a compound structure (e.g., 别穿帮).