Sound waves with frequencies below the audible range for humans, typically below 20 Hz.

Waves that are below the frequency of human hearing, often used in geological studies.

अवान्तर तरंगें

English Usage: Infrasonic waves can be generated by natural events such as earthquakes.

Hindi Usage: अवान्तर तरंगें प्राकृतिक घटनाओं जैसे भूकंप द्वारा उत्पन्न की जा सकती हैं।