litmus test


Definition of litmus test

: a test in which a single factor (such as an attitude, event, or fact) is decisive

Litmus Test Has Scientific Origins

It was in the 14th century that scientists discovered that litmus, a mixture of colored organic compounds obtained from lichen, turns red in acid solutions and blue in alkaline solutions and, thus, can be used as an acid-base indicator. Six centuries later, people began using litmus test figuratively. It can now refer to any single factor that establishes the true character of something or causes it to be assigned to one category or another. Often it refers to something (such as an opinion about a political or moral issue) that can be used to make a judgment about whether someone or something is acceptable or not.

Examples of litmus test in a Sentence

The party is using attitudes about gun control as a litmus test for political candidates.
Recent Examples on the Web School choice should become something of a litmus test for Republican candidates, and is an issue that can unite voters on both sides of the aisle, Luke Messer, president of the Invest in Education Foundation told Fox News Digital. Kelsey Koberg, Fox News, 22 Sep. 2022 Then fueled Smith during the ultimate litmus test, a futures tournament in Lubbock, Texas. San Diego Union-Tribune, 10 Sep. 2022 Krause said playing and beating a team like Wayne, which was co-champion of the Greater Western Ohio Conference (GWOC) last season, was a solid litmus test for the new nine-game Greater Miami Conference schedule, which begins next week. The Enquirer, 19 Aug. 2022 Coming out of the break, last weekend’s three-game series against the A.L. West-leading Houston Astros was to be a litmus test. Kurt Streeter, New York Times, 25 July 2022 The ending in All This Could Be Different can also serve, in my opinion, as a litmus test for how hopeful or pessimistic an individual reader might be. Emma Specter, Vogue, 18 Aug. 2022 Walmart’s latest earnings report can be looked at as a litmus test for retailers trying to figure out consumer sentiments amid rising inflation and uncertain economy. Fortune, 18 Aug. 2022 But those in the know are aware that the fixture arrives as a true litmus test to measure where Xavi's young outfit truly are in their evolution at this moment in time, amid a string of positive results as of late. Tom Sanderson, Forbes, 20 Mar. 2022 The race was seen as yet another litmus test of Trump's power and a harbinger of the state GOP. Stacey Barchenger, The Arizona Republic, 2 Aug. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'litmus test.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of litmus test

1913, in the meaning defined above

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The first known use of litmus test was in 1913

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Last Updated

27 Sep 2022

Cite this Entry

“Litmus test.” Dictionary, Merriam-Webster, Accessed 7 Oct. 2022.

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