- a radio wave shorter than that used in AM broadcasting, corresponding to frequencies of over 1600 kilohertz: used for long-distance reception or transmission.
- shortwave radio.
- a wave of electromagnetic radiation equal in length to, or shorter than, the wavelength of visible light.
- of, relating to, or using shortwaves.
- to transmit by shortwaves.
- a radio wave with a wavelength in the range 10–100 metres
- (as modifier)
