1.
radio waves, electromagnetic waves
Electromagnetic radiation used for communication, broadcasting, and other technological applications.
2.
signal, reception (informal)
In casual usage, refers to the quality of wireless signal reception.
TECHNICAL USE:
- 電波を発信する (to transmit radio waves)
- 電波を受信する (to receive radio waves)
- 電波障害 (radio interference)
- 電波法 (Radio Law)
EVERYDAY USE:
SLANG (dated): 電波系 was used to describe someone who seems disconnected from reality or has strange ideas (not recommended to use).
SCIENCE: 電波 is part of the electromagnetic spectrum, with frequencies lower than infrared.