decibel

 
Pronunciation: /ˈdɛsɪbɛl/
(abbreviation: dB)

noun

  • a unit used to measure the intensity of a sound or the power level of an electrical signal by comparing it with a given level on a logarithmic scale.
  • (in general use) a degree of loudness: his voice went up several decibels

Origin:

early 20th century: from deci- 'ten' + bel (the unit being one tenth of a bel)