An electric cord used to extend the length of a power cord WordNet 3.0 & Open English WordNet

An extension cord, extension cable, power extender, drop cord, or extension lead is a length of flexible electrical power cable with a plug on one end and one or more sockets on the other end. Wikipedia

Power cable with a plug on one end and one or more sockets on the other end Wikipedia Disambiguation

Flexible electrical power cable with a plug on one end and one or more sockets on the other end Wikidata

An electrical cord with a plug one end, and a single socket or a multi-port socket at the other end, used for powering one or more devices at a distance, too far from the wall outlet to be reached by the normal cords of the device or devices. Wiktionary

An electrical cord. Wiktionary (translation)