Of radio waves, having a wavelength of approximately 100 to 1000 meters(adjective)
Of radio equipment, capable of transmitting or receiving signals at such a wavelength.(adjective)
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Use "mediumwave" in a sentence
"That reply should have been addressed to Mark. mediumwave says:"
"I am deeply thankful to the US armed forces that make it possible for Al, Neenee, and, indeed, all preening blowhards everywhere to enjoy a safe and blessedly peaceful Memorial Day. mediumwave says:"
"In other areas, however, it is already declining in importance as television, FM, and mediumwave"