calibration component

https://doi.org/10.1351/goldbook.C00776
A component of a calibration mixture, present in the gaseous or vapour state, quantitatively and qualitatively defined, and used directly for testing and for calibration.
Source:
PAC, 1990, 62, 2167. 'Glossary of atmospheric chemistry terms (Recommendations 1990)' on page 2177 (https://doi.org/10.1351/pac199062112167)