decibels

n. unit of measurement for gauging the intensity of sound

The decibel (dB) is a logarithmic unit of measurement that expresses the magnitude of a physical quantity (usually power) relative to a specified or implied reference level. Its logarithmic nature allows very large or very small ratios to be represented by a convenient number, in a similar manner to scientific notation. Being essentially a ratio, it is a dimensionless unit. Decibels are useful for a wide variety of measurements in acoustics, physics, electronics and other disciplines.
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Noun
1. a logarithmic unit of sound intensity; 10 times the logarithm of the ratio of the sound intensity to some reference intensity
(synonym) dB
(hypernym) sound unit

n. decibel

DECIBEL