English Words Starting With R

• radio direction finder

  nounLow-frequency term; used in specific technical, maritime, aviation, and historical contexts.
  /ˈreɪ.di.əʊ dɪˈrek.ʃən ˌfaɪn.dər/An electronic device that determines the direction from which a radio signal is coming.
• radio free europe/radio liberty

  nounMedium
  /ˌreɪdiəʊ friː ˈjʊərəp/ /ˌreɪdiəʊ ˈlɪbəti/A U.S. government-funded organization providing uncensored news, information, and analysis to countries where a free press is banned or not fully established, historically focused on the former Soviet bloc.
• radio frequency

  nounC1/C2
  /ˈreɪdiəʊ ˈfriːkwənsi/A rate of oscillation in the range of electromagnetic waves suitable for communication via radio, typically between 3 kHz and 300 GHz.
• radio galaxy

  nounC2/Highly Specialized
  /ˈreɪdiəʊ ˌɡæləksi/A type of galaxy that emits exceptionally strong radio waves from its central regions.
• radio horizon

  nounLow
  /ˈreɪdiəʊ həˈraɪzn̩/The maximum distance at which a line-of-sight radio signal can travel, limited by the curvature of the Earth.
• radio interferometer

  nounC2
  /ˈreɪdiəʊ ˌɪntəfəˈrɒmɪtə/A scientific instrument that combines signals from multiple radio telescopes to simulate a much larger telescope, used to achieve high-resolution images of astronomical objects.
• radio knife

  nounC2/Professional
  /ˈreɪ.di.əʊ naɪf/A surgical instrument that uses high-frequency radio waves to cut tissue while simultaneously cauterizing blood vessels.
• radio microphone

  nounB2
  /ˈreɪdiəʊ ˈmaɪkrəfəʊn/A microphone that transmits sound wirelessly via radio waves to a receiver, typically used to allow freedom of movement for the speaker or performer.
• radio receiver

  nounB2
  /ˈreɪ.di.əʊ rɪˈsiː.vər/A device that receives radio waves and converts them into audible sound or other usable signals.
• radio shack

  nounLow
  /ˈreɪ.di.əʊ ʃæk/A small, often amateurish or makeshift building or room used for housing radio equipment and operations, typically for amateur (ham) radio.
• radio silence

  nounC1
  /ˈreɪdiəʊ ˈsaɪləns/A period during which no radio transmissions are made; a state of complete communication cessation from a person or group.
• radio source

  nounC2
  /ˈreɪ.di.əʊ sɔːs/A physical object or region in space that emits detectable radio waves.
• radio spectrum

  nounC1
  /ˈreɪdiəʊ ˈspɛktrəm/The range of all possible frequencies of electromagnetic radiation used for radio communication.
• radio star

  nounC1
  /ˈreɪdiəʊ stɑː/A famous or popular presenter, disc jockey, or performer on radio broadcasts.
• radio station

  nounB1
  /ˈreɪ.di.əʊ ˌsteɪ.ʃən/An organization or facility that broadcasts audio programming via radio waves.
• radio taxi

  nounMedium
  /ˈreɪdiəʊ ˌtæksi/A taxi that can be booked by radio or phone, often belonging to a fleet operated from a central office.
• radio telescope

  nounC1
  /ˈreɪdiəʊ ˈtɛlɪskəʊp/A scientific instrument that collects and measures radio waves emitted by celestial objects in space.
• radio tube

  nounC1
  /ˈreɪdiəʊ ˌtjuːb/A sealed glass container with a vacuum or special gas, containing electrodes, used to amplify, switch, or otherwise control electrical signals in early radio and electronic equipment.
• radio valve

  nounC2
  /ˈreɪdiəʊ ˌvælv/A vacuum tube used in early electronic equipment, especially radios, to control the flow of electrical current.
• radio wave

  nounB2
  /ˈreɪ.di.əʊ ˌweɪv/An electromagnetic wave used for transmitting radio signals through space.

Showing 241–260 of 5802 words.