noun

The word "adaptor" (or "adapter" in American English) refers to a device or tool that allows different components or systems to work together by changing or converting their connections or interfaces. For example, a power adaptor changes the voltage of electrical power to a level suitable for a particular device, or a plug adaptor allows a device to be plugged into different types of sockets.

example

1. I need to buy an adapter to connect my laptop to the projector.
2. His cell phone charger requires an adapter to plug into the outlet.
3. I bought an adapter so I could use my old headphones with my new device.