The test portion or test solution used for calibration of an analytical procedure. The calibration sample is normally of known weight or volume and is prepared according to specifications.
See also: test portion, test solution (in analysis), measurement solution (in analysis)
Source:
PAC, 1989, 61, 1657. 'Nomenclature for automated and mechanised analysis (Recommendations 1989)' on page 1660 (https://doi.org/10.1351/pac198961091657)