防伪 (fáng wěi) literally combines 防 (fáng), meaning 'to prevent' or 'to guard against', and 伪 (wěi), meaning 'fake' or 'counterfeit'. Together, they form a noun meaning 'anti-counterfeiting' — referring to measures, technologies, or systems designed to detect, deter, or prevent the production or sale of fake goods. It is commonly used in contexts involving product authenticity, especially for high-value or safety-critical items like medicines, luxury goods, official documents, and branded electronics.

The term often appears as part of compound nouns such as 防伪技术 (fángwěi jìshù, 'anti-counterfeiting technology'), 防伪标签 (fángwěi biāoqiān, 'anti-counterfeiting label'), or 防伪码 (fángwěi mǎ, 'anti-counterfeiting code'). It functions almost exclusively as a modifier or head noun in technical or regulatory discourse, rarely used alone without a supporting noun.