‘见鬼’ (jiàn guǐ) literally means 'to see a ghost', but as an interjection, it expresses strong disbelief, frustration, or annoyance—similar to English exclamations like 'nonsense!', 'bull!', or 'damn it!'. The phrase draws on the cultural association of ghosts with the impossible, absurd, or deeply unsettling; thus, encountering one symbolizes something so unbelievable or irritating that it feels surreal.

This expression is informal and emotionally charged, used mainly in spoken Mandarin among friends or in moments of exasperation. It’s not appropriate in formal settings or when speaking to elders or superiors. While the characters individually mean 'see' and 'ghost', the compound functions idiomatically—its meaning cannot be deduced from the parts alone. It often appears at the beginning or end of a sentence, sometimes repeated ('见鬼见鬼！') for emphasis, and may be softened with particles like 啊 or 呀 in casual speech.