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infrasonic

[in-fruh-son-ik]

adjective

noting or pertaining to a sound wave with a frequency below the audio-frequency range.

Origin of infrasonic

First recorded in 1925–30; infra- + sonic
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Word Origin and History for infrasonic
adj.

1927, from infra- + sonic.

Online Etymology Dictionary, © 2010 Douglas Harper
infrasonic in Medicine

infrasonic

[ĭn′frə-sŏn′ĭk]

adj.

Generating or using waves or vibrations with frequencies below that of audible sound.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
infrasonic in Science

infrasound

[ĭn′frə-sound′]

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.
Related formsinfrasonic adjective
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.