test sample

The sample, prepared from the laboratory sample, from which test portions are removed for testing or for analysis.
PAC, 1990, 62, 1193. 'Nomenclature for sampling in analytical chemistry (Recommendations 1990)' on page 1206 (https://doi.org/10.1351/pac199062061193)
See also:
PAC, 1988, 60, 1461. 'Nomenclature, symbols, units and their usage in spectrochemical analysis-X. Preparation of materials for analytical atomic spectroscopy and other related techniques (Recommendations 1988)' on page 1465 (https://doi.org/10.1351/pac198860091461)