coupler

noun

1. 1

   Someone who couples things together, especially someone whose job it is to couple railway carriages.

2. 2

   Anything that serves to couple things together; but especially a device that couples railway carriages.

3. 3

   A device that connects two keyboards of an organ together so that they play together.

4. 4

   A device used to convert electronic information into audible sound signals for transmission over telephone lines.

5. 5

   An electrical device used to transfer energy from one electric device to another, especially without a physical connection.