Almost always appears in the form 白种人 (báizhǒngrén, 'white-race person'). The full anthropological term is 高加索人种 (Gāojiāsuǒ rénzhǒng, 'Caucasian race') or 欧罗巴人种 (Ōuluóbā rénzhǒng, 'Europoid race').
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Used neutrally in Chinese discourse — race-talk doesn't carry the same charge as in English. Still, 白人 (báirén) is more colloquial and far more common in everyday speech.