dongle

Meanings

1. Any small device that plugs into an electronic device, typically a computer, and alters its functionality. Common examples include wireless modems, digital media players, software copy protect devices, and adapters.
2. A hardware device used by a specific application for purposes of copy protection.

Etymology

Unknown. Likely a descendant of dangle, reflecting that electronic accessories such as computer peripherals often are plugged in via a flexible cable (although wirelessness is also often relevant). Claims that the word comes from a man named "Don Gall" were made up by an advertisement. First usage 1980-1985.