A quantitative term to describe the (lack of) accuracy of a @C01030@; comprises the @I02991@ and the @M03796@. Inaccuracy must be viewed as a two-component quantity (vector); imprecision and @M03796@ should never be combined to give a scalar measure for chemical measurement process inaccuracy. (One or the other component may, however, be negligible under certain circumstances.) Inaccuracy should not be confused with uncertainty. Inaccuracy (imprecision, @M03796@) is characteristic of the measurement process, whereas error and uncertainty are characteristics of a result. (The latter characteristic, of course, derives from the imprecision and bounds for @M03796@ of the chemical measurement process.)