防盗 (fáng dào) literally combines 防 (fáng, 'to prevent' or 'to guard against') and 盗 (dào, 'theft' or 'stealing'). Together, it means 'anti-theft' — describing measures, devices, or features designed to deter or prevent theft. It functions primarily as an adjective (e.g., 防盗门 'anti-theft door') but can also act as a noun when referring to anti-theft systems collectively (e.g., 安装防盗 'installing anti-theft [measures]').

This term appears frequently in security contexts: building design (doors, windows), electronics (防盗报警器 'anti-theft alarm'), transportation (防盗锁 'anti-theft lock'), and digital services (防盗链 'anti-hotlinking'). It is neutral in register and widely used in both spoken and written Chinese, especially in urban, safety-related discourse. Unlike standalone verbs like 防止 or 阻止, 防盗 is almost always attributive or nominal — you rarely say '我防盗' (I anti-theft); instead, you say '我安装了防盗系统' (I installed an anti-theft system).