Infrasonics definitions

infrasonics

vibrational or stress waves in elastic media, having a frequency below those of sound waves that can be detected by the human ear—i.e., below 20 ... [1 related articles]
Found on http://www.britannica.com/eb/a-z/i/22

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infrasonics

the branch of science that deals with infrasonic phenomena.
Found on https://www.infoplease.com/dictionary/infrasonics

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