- The pressure that sound waves exert on an area or surface. For example, the minute fluctuations in atmospheric pressure resulting from the passage of a sound wave.
- The sound pressure (1) for a specific area. May be expressed, for instance, in dynes per square centimeter, or newtons per square meter.
- The value obtained when squaring multiple instantaneous sound pressure level measurements at a given point, averaging these over the time of a complete cycle, and taking the square root of this average. Usually expressed in pascals, though also expressed in other units, such as dyne/cm2, or microbars. Also called RMS sound pressure, effective sound pressure, or acoustic pressure.