any frequency between normally audible sound waves and the infrared light portion of the spectrum, lying between c. 10 kilohertz and c. 1,000,000 megahertz
See radio frequency in American Heritage Dictionary 4
noun Abbr. RF
The frequency of the waves transmitted by a specific radio station.
A frequency in the range within which radio waves may be transmitted, from about 3 kilohertz to about 300,000 megahertz.