Compare with density . The mass of a unit volume of a substance relative to the mass of a unit volume of water. Temperature must be specified when reporting specific gravities, since the density of the substance and of water change with temperature. Compare with density . The volume of a unit mass of substance.
Specific volume is the reciprocal of density.
The standard deviation is a statistical measure of precision. Compare with random error , gross error and mistake . Systematic errors have an identifiable cause and affect the accuracy of results. Compare with accuracy . A standard for comparison in measurements.