shortwave

An electromagnetic wave with a relatively short wavelength; specifically, one with a wavelength generally between 10 and 100 metres, corresponding to a frequency between 3 and 30 megahertz.

A waveband comprising radio waves in the shortwave frequency range, especially when used in broadcasting.

In full shortwave radio: a radio which is able to receive radio waves in the shortwave waveband.

Downward radiation in the shortwave frequency range which enters the Earth's atmosphere.

Of a radio wave: having a wavelength of between 10 and 100 metres, corresponding to a frequency between 3 and 30 megahertz.

Of radio equipment: capable of receiving or transmitting radio signals at wavelengths in the above range.

Using radio waves having wavelengths of between 10 and 100 metres, corresponding to frequencies between 3 and 30 megahertz.