speed of sound; sonic speed
Scientific and everyday term for the speed at which sound travels through a medium. Often used in compounds like 音速の壁 (sound barrier) or 超音速 (supersonic).
The jet flew faster than the speed of sound.
The speed of sound in air is about 340 meters per second.
The airplane exceeded the speed of sound.
The pilot broke the sound barrier.
音速 is the speed of sound while 光速 is the speed of light, two very different physical constants that learners sometimes mix up.
音速 means the ordinary speed of sound, while 超音速 means speeds that exceed it—learners often mix up the two similar-looking terms.
Compound of 音 (おん, 'sound') and 速 (そく, 'speed'). A straightforward Sino-Japanese technical term.