鉴别 (jiàn bié) means 'to differentiate or distinguish' but specifically through careful, expert examination — it implies appraising authenticity, quality, or value (e.g., of antiques, documents, products). This sets it apart from more general words like 辨别 (biàn bié) and 分辨 (fēn biàn), which simply mean 'tell apart', and from 识别 (shí bié), which focuses on recognition/identification. 鉴别 carries a sense of professional judgment or scrutiny.