(1) A logarithmic unit of sound intensity; 10 times the logarithm of the ratio of the sound intensity to some reference intensity
WiktionaryText
Noun
a common measure of sound intensity that is 1 tenth of a bel on the logarithmic intensity scale. It is defined as dB = 10 * log10(P 1/P 2), where P1 and P2 are the relative powers of the sound.
