background indication

https://doi.org/10.1351/goldbook.08007

Indication obtained from a phenomenon, body, or substance similar to the one under investigation but for which a quantity of interest is supposed not to be present or is not contributing to the indication.

Note: In VIM 4.2, this concept is termed "blank indication" with "background indication" as an alternate term. However, since blank indication refers to the explicit use of a blank material in analytical chemistry, it should be distinguished from the concept "background indication".

Source:
PAC, 2021, 93, 997. 'Metrological and quality concepts in analytical chemistry (IUPAC Recommendations 2021)' on page 1001 (https://doi.org/10.1515/pac-2019-0819)