The definition of a decibel is a degree of loudness, or is a unit used to measure how powerful or loud a sound or signal is using a logarithmic formula.(noun)
When you turn your iPod up as loud as it can possibly go, this is an example of when you listen to your music at the highest decibel.
See decibel in Webster's New World College Dictionary
Origin: deci- + bel
See decibel in American Heritage Dictionary 4
noun Abbr. dB
Origin: + bel.
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