Low frequency

radio wave having a long wavelength

Low Frequency or LF refers to Radio Frequencies (RF) in the range of 30 kHz–300 kHz. In Europe, and parts of  Northern Africa and of Asia, part of the LF spectrum is used for AM broadcast service. In the western hemisphere, its main use is for aircraft beacon, navigation (LORAN), information, and weather systems. Time signal stations MSF, DCF77, JJY and WWVB are found in this band. Also known as the kilometer band or kilometer wave as the wavelengths range from ten to one kilometers.
See more at Wikipedia.org...

Noun
1. 30 to 300 kilohertz
(synonym) LF
(hypernym) radio frequency
(part-holonym) electromagnetic spectrum
2. a pitch that is perceived as below other pitches
(synonym) low pitch
(hypernym) pitch
(hyponym) deepness

Any frequency in the band from 30 kHz to 300 kHz. (188 )

The frequency band between 30 and 300 kHz. (FAA4)