decibel

noun
deci·​bel | \ˈde-sə-ˌbel, -bəl\

Definition of decibel 

1a : a unit for expressing the ratio of two amounts of electric or acoustic signal power equal to 10 times the common logarithm of this ratio

b : a unit for expressing the ratio of the magnitudes of two electric voltages or currents or analogous acoustic quantities equal to 20 times the common logarithm of the voltage or current ratio

2 : a unit for expressing the relative intensity of sounds on a scale from zero for the average least perceptible sound to about 130 for the average pain level

3 : degree of loudness also : extremely loud sound usually used in plural

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Did You Know?

The unit for measuring the relative intensities of sound is called a decibel. Because the decibel scale is logarithmic, a sound with an intensity that is twice that of a reference sound corresponds to an increase of little more than 3 decibels. In common practice, the reference point of 0 decibel is set at the intensity of the least perceptible sound, the threshold of hearing. On such a scale a 10-decibel sound is 10 times the intensity of the reference sound; a 20-decibel sound is 100 times the reference intensity, and so on. Normal conversation is usually around 60 decibels, an electric saw around 100 decibels, and amplified rock music around 120 decibels.

Examples of decibel in a Sentence

a rock concert blasting music at 110 decibels the crowd decibels increased dramatically as the horses neared the finish line

Recent Examples on the Web

West’s party didn’t even start until 9:30 p.m. and that the volume was cranked up to 120 decibels, according to the gossip site. Ryan Gaydos, Fox News, "Kanye West event leads to Wyoming ranch banning rap parties," 7 June 2018 But the roar from the Hogs’ legendarily loud exhaust pipes might sound several decibels lower this year. Stephen Hudak, OrlandoSentinel.com, "Harley-Davidson sales slip but loyalty is strong among Leesburg Bikefest throngs," 27 Apr. 2018 Sounds like crushing stone, excavation, sawing, and boilers and furnaces hover around 100 to 109 decibels, loud enough to cause hearing loss after 15 minutes of exposure. Kate Wagner, The Atlantic, "City Noise Might Be Making You Sick," 20 Feb. 2018 A hundred and eighty, mark you, and not a decibel less! Anthony Lane, The New Yorker, "Bill Clinton and James Patterson’s Concussive Collaboration," 3 June 2018 In 2004, telecommunications officials established a standard for cellphones sold in South Korea to make shutter sounds above 60 decibels when used to take pictures, even on silent mode. Eun-young Jeong, WSJ, "Creep Sweep: Spy Squad, Politicians Target South Korea’s Peeping Toms," 2 June 2018 The loud, sellout crowd is expected to be a couple of decibels higher with Joel Embiid making his first home playoff appearance. Keith Pompey, Philly.com, "Sixers, returning home for Game 5, look to close out series vs. Heat," 23 Apr. 2018 On the Big Island, mongoose have proliferated, devastating local bird populations; so have Puerto Rican coquí frogs, which chirp abruptly and erratically at 90 decibels, like a mobile infestation of alarm clocks. Jennifer Kahn, New York Times, "Should Some Species Be Allowed to Die Out?," 13 Mar. 2018 Battalion The music’s thumping at club decibels, a Medusa-like chandelier hangs over the cocktail bar and Spurs coach Gregg Popovich is holding court on opening night. Mike Sutter, San Antonio Express-News, "San Antonio’s Top 9 restaurants," 4 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'decibel.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of decibel

1928, in the meaning defined at sense 1a

History and Etymology for decibel

International Scientific Vocabulary deci- + bel

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Dictionary Entries near decibel

deci-

Decian

deciare

decibel

decidable

decide

decide against

Statistics for decibel

Last Updated

25 Oct 2018

Look-up Popularity

Time Traveler for decibel

The first known use of decibel was in 1928

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More Definitions for decibel

decibel

noun

English Language Learners Definition of decibel

: a unit for measuring how loud a sound is

decibel

noun
deci·​bel | \ˈde-sə-ˌbel, -bəl\

Kids Definition of decibel

: a unit for measuring the loudness of sounds

decibel

noun
deci·​bel | \ˈdes-ə-bəl, -ˌbel \

Medical Definition of decibel 

1a : a unit for expressing the ratio of two amounts of electric or acoustic signal power equal to 10 times the common logarithm of this ratio

b : a unit for expressing the ratio of the magnitudes of two electric voltages or currents or analogous acoustic quantities equal to 20 times the common logarithm of the voltage or current ratio

2 : a unit for expressing the relative intensity of sounds on a scale from zero for the average least perceptible sound to about 130 for the average pain level

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Comments on decibel

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