An electronic key is a digital or wireless device used to unlock doors, gates, vehicles, or secure systems without a traditional metal key. The term combines four characters: 电 (diàn, 'electricity' or 'electronic'), 子 (zǐ, a common suffix for small or modern objects, like 'device'), 钥 (yào, 'key' in the sense of unlocking), and 匙 (shi, 'spoon' but here used as a bound morpheme meaning 'key'—together 钥匙 means 'key'). While 钥匙 alone means 'physical key', adding 电子 specifies it's digital—such as an RFID card, smartphone app, or key fob.

This term is widely used in modern urban settings: apartment buildings with access control, shared offices, smart homes, and car keyless entry systems. It reflects China’s rapid adoption of smart infrastructure, where convenience and security are balanced through technology. Unlike physical keys, electronic keys can be duplicated digitally, revoked remotely, or linked to user accounts.