the.com/subsonic
Moving slow enough that you never beat your own noise to the party.
means Traveling slower than the speed of sound, roughly 767 mph at sea level.
from Latin sub (under) plus sonic (sound), coined in the 1930s as engineers raced toward the sound barrier and needed a word for everything below it.
Speed limitMach 0.8 and below counts as comfortably subsonic.
Bullet trickSubsonic ammo skips the loud supersonic crack.
Sound's paceSpeed varies with air temperature, not pressure.