- sound with frequencies below the audible range.
Origin of infrasound
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- soundlike waves having a frequency below the audible range, that is, below about 16Hz
- Sound whose wave frequency is too low (under 15-20 hertz) to be heard by humans. Some animals, such as elephants and whales, emit calls at infrasound frequencies. See Note at ultrasound.
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