Wiktionary
extension cable
n. A cable that can be used to extend a signal or power cable or move the connexion point for a signal or power source.
Usage examples of "extension cable".
Louren was the first to move, he scrambled to his feet and snatched up one of the electric bulbs in its little wire cage, the extension cable slithered after him like a snake as he went forward.
If we have to, we could treat this as a normal-space haul of explosive cargo, and let it out on the long-reach extension cable.
He attached the short extension cable to the lower pulley of the Trotter MG2100 total fitness machine.
An extension cable lay on the study floor beside the desk, but it had been disconnected from the mains supply.
Mike put an extension cable on the TV so that we could watch Home Improvement tapes outdoors.