decibel

American  

[des-uh-bel, -buhl] / ˈdɛs əˌbɛl, -bəl /

noun

Physics.

1. a unit used to express the intensity of a sound wave, equal to 20 times the common logarithm of the ratio of the pressure produced by the sound wave to a reference pressure, usually 0.0002 microbar.

2. a unit of power ratio, the number of units being equal to a constant times the logarithm to the base 10 of the intensities of two sources.

3. a unit used to compare two voltages or currents, equal to 20 times the common logarithm of the ratio of the voltages or currents measured across equal resistances. dB, db

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decibel British  

/ ˈdɛsɪˌbɛl /

noun

1. a unit for comparing two currents, voltages, or power levels, equal to one tenth of a bel

2. a similar unit for measuring the intensity of a sound. It is equal to ten times the logarithm to the base ten of the ratio of the intensity of the sound to be measured to the intensity of some reference sound, usually the lowest audible note of the same frequency

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decibel Scientific  

/ dĕs′ə-bəl /

1. A unit used to measure the power of a signal, such as an electrical signal or sound, relative to some reference level. An increase of ten decibels in the power of a signal is equivalent to increasing its power by a factor of ten. As a measure of sound intensity, a zero-decibel reference is stipulated to be the lowest level audible to the human ear; the speaking voice of most people ranges from 45 to 75 decibels.

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decibel Cultural  

1. A unit of measurement of the volume of sounds.

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Etymology

Origin of decibel

First recorded in 1925–30; deci- + bel ¹

Example Sentences

“It’s insane. I can’t explain it,” Koy adds, staring up at the stadium’s glass roof, preparing to crack it with decibels of laughter.

From Los Angeles Times

It blares at 113 decibels, on par with a rock concert.

From The Wall Street Journal

Will Ashworth, founder of Watergate Bay Hotel and SeaSpace, said raising levels to 65 decibels would represent "a very significant additional level of sound" that would impact businesses, campsites and residents.

From BBC

But on Monday night in Cleveland’s Rocket Arena, where the familiar chant reached arena-filling decibels, it felt different.

From Los Angeles Times

The numbers that were perhaps most telling though were on the Twickenham decibel meter, showing the love for a team that has not always felt it.

From BBC