# correction

From EngHydroDic

A quantity which is applied to an observation or function thereof, to diminish or eliminate the effects of errors and obtain an improved value of the observation or function. It is also applied to reduce an observation to some arbitrary standard. The correction corresponding to a given error is of the same magnitude but of opposite sign. See chronometer correction, dip correction, index correction, instrumental correction, lead line correction, parallax correction, personal correction, polaris correction, refraction correction, semidiameter correction, sextant altitude correction, sky wave correction, orthometric correction, tidal difference.