sub·​son·​ic ˌsəb-ˈsä-nik How to pronounce subsonic (audio)
: of, relating to, or being a speed less than that of sound in air
: moving, capable of moving, or utilizing air currents moving at a subsonic speed
subsonically adverb

Examples of subsonic in a Sentence

Recent Examples on the Web At subsonic speeds, the airflow around the wings, tail, and fuselage is smooth. Jacek Krywko, Ars Technica, 29 Mar. 2024 Today’s regulations against sonic booms would mean subsonic Overture flights over most major land masses, throttling up only over ocean transits. Tim Stevens, The Verge, 22 Mar. 2024 While Russian air defenses struggled to shoot down supersonic HIMARS rockets, Storm Shadow is a subsonic cruise missile—a class of weapon that Ukraine’s own air defense system has become efficient at shooting down. Sébastien Roblin, Popular Mechanics, 12 May 2023 The house was littered with casings from subsonic ammunition of the same brand recovered from the motel room, Avila said. Matthew Ormseth, Los Angeles Times, 5 Dec. 2023 See all Example Sentences for subsonic 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'subsonic.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


International Scientific Vocabulary

First Known Use

1920, in the meaning defined at sense 3

Time Traveler
The first known use of subsonic was in 1920

Dictionary Entries Near subsonic

Cite this Entry

“Subsonic.” Dictionary, Merriam-Webster, Accessed 25 Jul. 2024.

Kids Definition


sub·​son·​ic ˌsəb-ˈsän-ik How to pronounce subsonic (audio)
: of, relating to, or being a speed less than that of sound in air
: moving, capable of moving, or using air currents moving at a subsonic speed
Last Updated: - Updated example sentences
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