sonic

/ˈsɑnɪk/

/ˈsɒnɪk/

Other forms: sonically

The adjective sonic means related to audible sound or to the speed of sound waves. If something goes faster than the speed of sound, it creates a sonic boom, a shock wave that sounds like an explosion.

The adjective sonic was coined in the 1920s, from the Latin sonus, or "sound." Ever since, it's been used not only to describe things relating to sound, but also things that travel as fast as sound. The Sonic fast food chain originally advertised "Service With the Speed of Sound." A super-fast Japanese express train is called Sonic. And the Sonic the Hedgehog video games feature a speedy main character.

Definitions of sonic

1. adjective

   (of speed) having or caused by speed approximately equal to that of sound in air at sea level
   “a sonic boom”

   synonyms: transonic

   antonyms:

   subsonic

   (of speed) less than that of sound in a designated medium

   supersonic

   (of speed) greater than the speed of sound in a given medium (especially air)
2. adjective

   relating to audible sound
   “a sonic wave”

   synonyms:

   audible, hearable

   heard or perceptible by the ear