Audiovisual (AV) means possessing both a sound and a visual component, such as slide-tape presentations, films, television programs, church services and live theater productions.
In physics, sound is a vibration that typically propagates as an audible wave of pressure, through a transmission medium such as a gas, liquid or solid.
Sonorous metal blowing martial sounds, At which the universal host up sent A shout that tore hell's concave, and beyond Frighted the reign of Chaos and old Night.
John Milton, Paradise Lost (1667; 1674), Book I, line 540.
A thousand trills and quivering sounds In airy circles o'er us fly, Till, wafted by a gentle breeze, They faint and languish by degrees, And at a distance die.
