subsonic

[suhb-son-ik]

adjective

1. noting or pertaining to a speed less than that of sound in air at the same height above sea level.

2. infrasonic.

subsonic

/ sʌbˈsɒnɪk /

adjective

1. being, having, or travelling at a velocity below that of sound

   a subsonic aircraft

subsonic

1. Having a speed less than that of sound in a designated medium, usually air; having a velocity less than Mach 1.

2. Compare hypersonic supersonic transonic

Other Word Forms

• subsonically adverb

Word History and Origins

Origin of subsonic¹

1940–45; sub- + sonic ( def. )

Example Sentences

The Burevestnik, which flew at well below the speed of sound, made its debut just as subsonic missiles are increasingly being shot down in Ukraine because modern defensive systems can lock onto them.

Read more on The Wall Street Journal

Even then Tomahawks, which fly at subsonic speeds at a low altitude, could be vulnerable to Russian air defenses.

Read more on The Wall Street Journal

Right above the shores of Huntington Beach, a retired American subsonic T-33 fighter jet darted across the blue canvas of a clear afternoon sky, leaving a spiraling plume of smoke in its wake.

Read more on Los Angeles Times

In terms of purely destructive power, however, hypersonic missiles are not hugely different from supersonic or subsonic cruise missiles, according to Mr Freer.

Read more on BBC

They presented records showing that Peterson, who lived in Durham, N.C., bought silencer components online and researched subsonic ammunition, which is quieter than standard rounds.

Read more on Los Angeles Times