Precision - some definitions
1) ...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.
-- Last. A Dictionary of Epidemiology. 1988
OR
Precision in epidemiologic measurements corresponds to the reduction of random (or sampling) error.
-- Rothman. Modern Epidemiology. 1986.