A logarithmic unit of power, similar to dB m but computed from voltage measurements. The reference level is 1 volt. A voltage of V volts corresponds to a power of 20·log10(V) dB V
Russ Rowlett (Director), How Many? A Dictionary of Units of Measurement, Center for Mathematics and Science Education University of North Carolina, USA 2005. http://www.unc.edu/~rowlett/units/dictA.html, (Unit of Meas and Covr Factors - Amer) {608}