Solenoid
A loop of wire, often wrapped around a metal core, which produces a magnetic field when an electrical current is passed through it.
Also defined in 1 more source
An electrical component using a small amount of current flowing through a coil to produce a magnetic force that pulls an iron core into the center of the coil. The core may be attached to a set of heavy-duty electrical contacts, or it may be used to move a valve or other mechanical device.
Aviation Maintenance Technician Handbook — Airframe, p. G-32