The science of measuring colours and assigning them numeric values.(noun)
Analysis involving the quantitative measurement of colour.(noun)
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Use "colorimetry" in a sentence
"Page 418, Volume 3 physicists from the eighteenth to the twentieth century was the emergence of two new sciences; photometry and colorimetry, both arising with the evident purpose of measuring light first and color afterward."
"The important principles around which practically all quantitative methods may be grouped are: Neutralization, solubility-product, oxidation-reduction, colorimetry, and evolution and measurement of gases."
"Brief reviews of photometry, colorimetry, and brightness perception are presented as a foundation for the discussion of circadian light."