waveguide

n. device used to conduct and direct microwaves

A waveguide is a structure which guides waves, such as electromagnetic waves, light, or sound waves. There are different types of waveguide for each type of wave.
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A material medium that confines and guides a propagating electromagnetic wave. (188 ) Note 1: In the microwave regime, a waveguide normally consists of a hollow metallic conductor, usually rectangular, elliptical, or circular in cross section. This type of waveguide may, under certain conditions, contain a solid or gaseous dielectric material. Note 2: In the optical regime, a waveguide used as a long transmission line consists of a solid dielectric filament (optical fiber), usually circular in cross section. In integrated optical circuits an optical waveguide may consist of a thin dielectric film. Note 3: In the rf regime, ionized layers of the stratosphere and refractive surfaces of the troposphere may also act as a waveguide.

Noun
1. a hollow metal conductor that provides a path to guide microwaves; used in radar
(synonym) wave guide
(hypernym) conductor
(part-holonym) radar, microwave radar, radio detection and ranging, radiolocation