Carrier-sense multiple access with collision detection

In telecommunication, a carrier sense multiple access with collision detection (CSMA/CD) is a network control protocol in which (a) a carrier sensing scheme is used and (b) a transmitting data station that detects another signal while transmitting a frame, stops transmitting that frame, transmits a jam signal, and then waits for a random time interval before trying to send that frame again.

Source: from Federal Standard 1037C