key fob

Definitions

1. An item carried on a key ring either as decoration or for security.
2. A passive wireless electronic device that usually uses RFID technology to control access to buildings, containers, computers, etc. by being placed near a detector.
3. An active wireless electronic device that controls access to buildings or vehicles, such as a remote control for a car door lock.

Equivalents

Examples

“She finds her key fob and unlocks the doors.”

CEFR level