podcast vs radio

podcast

noun
  • A programme, especially an audio programme, produced on a regular basis, delivered over the Internet in a compressed digital format and designed for playback on computers or portable devices such as mobile phones. 

  • An individual episode of such a programme. 

verb
  • To deliver a programme, especially an audio programme, over the Internet on a regular basis for playback on computers or portable devices such as mobile phones. 

  • To deliver (information) in the form of a programme, especially an audio programme, over the Internet on a regular basis for playback on computers or portable devices such as mobile phones. 

radio

noun
  • The continuous broadcasting of sound via the Internet in the style of traditional radio. 

  • The technology that allows for the transmission of sound or other signals by modulation of electromagnetic waves. 

  • A device that can capture (receive) the signal sent over radio waves and render the modulated signal as sound. 

  • A device that can transmit radio signals. 

  • On-board entertainment system in a car, usually including a radio receiver as well as the capability to play audio from recorded media. 

verb
  • To order or assist (to a location), using telecommunications. 

  • To use two-way radio to transmit (a message) (to another radio or other radio operator). 

How often have the words podcast and radio occurred in a corpus of books? (source: Google Ngram Viewer )