Any means of communication using radio or other electromagnetic waves
Many stations broadcast on shortwaves.
Any frequency in this range, especially when used in broadcasting.
An electromagnetic wave having a wavelength between approximately 10 and 100 meters, corresponding to frequencies between 3 and 30 MHz.
Downward radiation entering the earth's atmosphere that is in the shortwave frequency range.
Having a wavelength of approximately 10 to 100 meters.
Capable of transmitting or receiving signals at such a wavelength.