翻车 (fān chē) is a separable verb (离合词) that literally means 'to overturn a vehicle'. In modern internet slang, it has taken on a vivid figurative sense meaning 'to fail spectacularly' or 'to have a major setback'—often used when a plan backfires, a livestream crashes, or someone makes an embarrassing mistake. The two syllables can split: 翻了车 (overturned the car), 翻过车 (have overturned a car), 翻一次车 (had one failure). Regional dialects also use it as a noun for a waterwheel or bird snare, but those are rare in standard Mandarin.