an error expressed in physical units

1. Shortest distance between the center of impact or the center of burst of a group of shots, and the point of impact or burst of a single shot within the group. 2. Error of a sight consisting of its error in relation to a master service sight with which it is tested, including the known error of the master service sight. Relative error, which is a part of absolute error, includes only the error of a sight in relation to a master service sight.... read full article

absolute uncertainty. Compare with relative error. The uncertainty in a measurement, expressed with appropriate units. For example, if three replicate weights for an object are 1.00 g, 1.05 g, and 0.95 g, the absolute error can be expressed as ¡3/4 0.05 g. Absolute error is also used to express inaccuracies; for example, if the "true value" is 1.11 g and the measured value is 1.00 g, the absolute error could be written as 1.00 g - 1.11 g = -0.11 g. Note that when absolute errors are associated with indeterminate errors, they are preceded with "¡3/4"; when they are associated with determinate errors, they are preceded by their sign.

the difference between a measured value and the true or accepted value.