sub·​son·​ic | \ˌsəb-ˈsä-nik \

Definition of subsonic 

1 : of, relating to, or being a speed less than that of sound in air

2 : moving, capable of moving, or utilizing air currents moving at a subsonic speed

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Other Words from subsonic

subsonically \ˌsəb-​ˈsä-​ni-​k(ə-​)lē \ adverb

Examples of subsonic in a Sentence

Recent Examples on the Web

In addition to operating intercontinental ballistic missile silos, the North Dakota base is home to the B-52 Stratofortress, the long-range heavy bomber capable of flying at high subsonic speeds and dropping nuclear warheads on enemy targets. Paul Sonne, Washington Post, "Air Force base that lost explosives: We’re also missing a machine gun," 18 May 2018 It was powered by a Teledyne Technologies J402 turbojet engine, which pushed the 14-foot-long cruise missile at subsonic speeds to distances of just over 200 miles. Kyle Mizokami, Popular Mechanics, "The Pentagon’s New Strike Missile Just Saw Its First Combat," 17 Apr. 2018 As a cruise missile, the DF-10A flies low and subsonic, ideally flying below enemy air defense radars. Kyle Mizokami, Popular Mechanics, "Asia’s Quiet Missile Race," 2 Jan. 2018 The plane is designed to hit 940 mph and cruise at around 55,000 feet, far higher than the typical 35,000 for subsonic airliners. Jack Stewart, WIRED, "NASA's Newest X-Plane Could Revive Supersonic Flight for the Masses," 3 Apr. 2018 The extended-range JSOW cruises at subsonic speeds rather than racing toward targets like an air-to-air missile. Joe Pappalardo, Popular Mechanics, "Hollywood Has No Idea How Nukes Work," 2 Apr. 2018 The system first detects and classifies a threat, determining if the threat is a supersonic tank round or subsonic missile or rocket. Kyle Mizokami, Popular Mechanics, "U.S. Army Tanks to Get Active Protection Systems by 2020," 10 Oct. 2017 Bullet-shaped with stubby wings and a Williams turbofan engine, the Tomahawk flies low at subsonic speeds to avoid enemy radar. Kyle Mizokami, Popular Mechanics, "The Tomahawk Cruise Missile Will Fly On Through At Least 2040," 13 June 2017 The long-range B-52 heavy bomber flies at subsonic speeds and provides a global strike capability. Allison Barrie, Fox News, "With North Korea warning of nuclear war, B-52s soar in 'Foal Eagle'," 4 Apr. 2013

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'subsonic.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of subsonic

1920, in the meaning defined at sense 3

History and Etymology for subsonic

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Time Traveler for subsonic

The first known use of subsonic was in 1920

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English Language Learners Definition of subsonic

: slower than the speed of sound

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the figure or shape of a crescent moon

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