1 The quality of being sharply defined or stated. One measure of precision is the number of distinguishable alternatives from which a measurement was selected, sometimes indicated by the number of significant digits in the measurement. Another measure of precision is the standard error of measurement, the standard deviation of a series of replicate determinations of the same quantity. Precision does not imply accuracy. 2 In statistics, precision is defined as the inverse of the variance of a measurement or estimate.