[{"Bold_text": "noun", "List Items": ["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.", "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.", "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. : d B, db"]}]