A decibel may refer to any of the following:
1. A decibel (dB) is a unit of measurement of voltage or another intensity. Decibels are one tenth of a bel.
2. Abbreviation for decibel, dBA is the noise power calculated in dB. 0 dBA is equal to 3.16 picowatts (-85 dBm).
3. A db is also sometimes used as an abbreviation for a database.