shortwave

[shawrt-weyv]
noun
  1. Electricity. a radio wave shorter than that used in AM broadcasting, corresponding to frequencies of over 1600 kilohertz: used for long-distance reception or transmission.
  2. shortwave radio.
  3. Physics. a wave of electromagnetic radiation equal in length to, or shorter than, the wavelength of visible light.
adjective
  1. of, relating to, or using shortwaves.
verb (used with or without object), short·waved, short·wav·ing.
  1. to transmit by shortwaves.

Origin of shortwave

First recorded in 1900–05; short + wave
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for short wave

short wave

noun
    1. a radio wave with a wavelength in the range 10–100 metres
    2. (as modifier)a short-wave broadcast
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

short wave in Science

shortwave

[shôrtwāv]
  1. A radio wave with a frequency between 5.9 megahertz and 26.1 megahertz. Shortwaves broadcast from the Earth's surface are reflected by the upper atmosphere and can travel great distances around the planet. The shortwave band of the electromagnetic spectrum is used for amateur radio communications.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.