sound wave

vibration in the air

vibrations in the air caused by sounding voices

Sound is a disturbance of mechanical energy that propagates through matter as a wave (through fluids as a compression wave, and through solids as both compression and shear waves). Sound is further characterized by the generic properties of waves, which are frequency, wavelength, period, amplitude, speed, and direction (sometimes speed and direction are combined as a velocity vector, or wavelength and direction are combined as a wave vector).
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Sound 1. a pressure wave propagating through an elastic medium; waves with a frequency of 20–20,000 Hz cause the sensation of hearing. 2. [more]Sound wave - Community and Resources

Noun
1. (acoustics) a wave that transmits sound
(synonym) acoustic wave
(hypernym) wave, undulation
(hyponym) air wave
(classification) acoustics

See acoustic wave.