Terahertz

Electromagnetic waves sent at terahertz frequencies, known as terahertz radiation, terahertz waves, terahertz light, T-rays, T-light, T-lux and THz, are in the region of the electromagnetic spectrum between 300 gigahertz (3x1011 Hz) and 3 terahertz (3x1012 Hz), corresponding to the submillimeter wavelength range between 1 millimeter (high-frequency edge of the microwave band) and 100 micrometres (long-wavelength edge of far-infrared light).
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Noun
1. one trillion periods per second
(synonym) THz
(hypernym) rate

A unit denoting one trillion (1012) hertz. (188 )