|1.||to wind or gather (ropes, hair, etc) into loops or (of rope, hair, etc) to be formed in such loops|
|2.||(intr) to move in a winding course|
|3.||something wound in a connected series of loops|
|4.||a single loop of such a series|
|5.||an arrangement of pipes in a spiral or loop, as in a condenser|
|6.||See also induction coil an electrical conductor wound into the form of a spiral, sometimes with a soft iron core, to provide inductance or a magnetic field|
|7.||an intrauterine contraceptive device in the shape of a coil|
|8.||the transformer in a petrol engine that supplies the high voltage to the sparking plugs|
|[C16: from Old French coillir to collect together; see |
chemical oxygen-iodine laser
in an electric circuit, one or more turns, usually roughly circular or cylindrical, of current-carrying wire designed to produce a magnetic field or to provide electrical resistance or inductance; in the latter case, a coil is also called a choke coil (see also inductance). A soft iron core placed within a coil produces an electromagnet. A cylindrical coil that moves a plunger within it by variations in the current through the coil is known as a solenoid (q.v.).
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