1. A wave produced by the oscillation of an electric charge or a wave in which there are both electric and magnetic displacements.
2. A transverse wave associated with the transmission of electromagnetic energy.

Instruments that consist of a magnet, generally rare earth (either samarium cobalt or neodymium iron boron), and an energizing coil.

The magnet is attached to the ossicular chain (any of certain small bones, as those of the middle ear), tympanic membrane, or the inner ear (round window or fenestra).

A fluctuating magnetic field is generated when the coil is energized by a signal, which corresponds to an acoustic input and this magnetic field causes the magnet to vibrate.

The vibrating magnet, in turn, causes movement of either the ossicular chain or the cochlear fluids directly.

The force generated is inversely proportional to the square of the distance between the coil and magnet (e.g., doubling the distance between the magnet and coil results in an output of one-fourth the force); therefore, these two components must be maintained in close proximity to one another to realize an efficient system.