fob
n. countable C1 Advanced US //ˈfɔb// UK //fˈɒb// fob
n. a small electronic device you use to open a car door or get into a building. It is also a short name for a key ring or a decorative item on a chain.
n. a small electronic device used for remote keyless entry or authentication; also refers to a decorative ornament attached to a watch chain or key ring.
I pressed the button on my key fob to unlock the car.
Employees must tap their security fob against the reader to gain access to the laboratory after hours.
The antique pocket watch was accompanied by a heavy gold fob, a family heirloom that had been passed down through four generations of watchmakers.
Usage
Commonly used in modern contexts to refer to electronic access tokens.