acid number

noun

: a measure of the amount of free acids (as fatty acids) in a substance (as an oil or resin) usually expressed as the number of milligrams of potassium hydroxide required to neutralize one gram of the substance

called also acid value

Word History

First Known Use

1886, in the meaning defined above

Time Traveler
The first known use of acid number was in 1886

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Cite this Entry

“Acid number.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/acid%20number. Accessed 28 Mar. 2023.

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