1. a device that receives and plays sounds broadcast through the air
2. the system of broadcasting sounds through electromagnetic waves
3. a device used for two-way communication by sending and receiving radio waves

1. to send a message using a radio

1. relating to or using radio waves

Examples

• She listened to music on the radio while driving to work.
• The news program airs on radio every morning at eight.
• The pilot used the radio to contact the control tower.
• Police officers radio for backup when needed.
• The ship sent a radio message to the coast guard.
• Radio waves travel at the speed of light.
• He works as a radio announcer at the local station.