The process of experimentally obtaining one or more quantity values that can reasonably be attributed to a quantity.

The process of experimentally obtaining one or more quantity values that can reasonably be attributed to a quantity.

From the International Vocabulary of Metrology – Basic and General Concepts and Associated Terms (VIM 3rd edition) JCGM 200:2012 http://www.bipm.org/en/publications/guides/vim.html

NOTE 1 Measurement does not apply to nominal properties. NOTE 2 Measurement implies comparison of quantities or counting of entities. NOTE 3 Measurement presupposes a description of the quantity commensurate with the intended use of a measurement result, a measurement procedure, and a calibrated measuring system operating according to the specified measurement procedure, including the measurement conditions.

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