The hobby or pastime of communicating by two-way radio, often striving for “DX” QSOs that are challenging because of distance.

(medicine) A surgical instrument that uses a high-frequency electric arc to cut through or cut away tissue and at the same time sterilize the edges of the wound and seal cut blood vessels.

The location of a radio transmitter by taking bearings from two receivers. / The location of a vessel or aircraft by taking bearings to two transmitters of known position.

A status maintained where all fixed or mobile radio stations in an area stop transmitting (sometimes limited to certain frequency bands). / The period of time during which this status exists.

The branch of astronomy which utilizes radio waves through the use of radio telescopes to study celestial bodies and occurrences.

Telemetry by use of radio waves.

plural of radio frequency

Of or pertaining to electromagnetic radiation in the radio frequency band of the spectrum.

(uncountable) That part of the electromagnetic spectrum, between about 3 kHz and 300 MHz, within which radio waves are transmitted. / (countable) A frequency in this range.

plural of radio beacon