lit·​mus | \ ˈlit-məs How to pronounce litmus (audio) \

Definition of litmus

1 : a coloring matter from lichens that turns red in acid solutions and blue in alkaline solutions and is used as an acid-base indicator
2 : the critical factor in a litmus test also : litmus test

Examples of litmus in a Sentence

Recent Examples on the Web But in too many of these cases, justice becomes lost in tortured litmus tests about the circumstances surrounding an officer’s response. Sharon Grigsby, Dallas News, "Families of those unjustly killed by cops in North Texas ask: Why were you not moved to act before now?," 10 June 2020 But a stunningly against Colorado laying -1.5 points Saturday night was a litmus-test loss that selection committees will long remember. Jeff Fogle, Los Angeles Times, "UCLA needs help but looking better for postseason as USC stumbles," 3 Feb. 2020 Activists, however, warned that the episode could serve as a litmus by the right-wing government of Prime Minister Viktor Orban to test whether anti-LGBT sentiments could be exploited politically in the same way Poland’s government has. Washington Post, "Coca-Cola featured same-sex couples in a Hungarian ad campaign. That has triggered calls for a boycott.," 6 Aug. 2019 New York’s Tere O’Connor is a litmus-test kind of choreographer., "‘Hansel and Gretel’ coming to opera houses," 5 Nov. 2019 Cristobal gets a chance on national television on Aug. 31 against Auburn to flex some of that muscle in a litmus-test game that is either going to catapult Cristobal’s profile into another stratosphere or bring him temporarily back to Earth. 4. John Canzano,, "John Canzano’s Top 25 most influential people in Oregon sports for 2019," 17 Aug. 2019 Newsom is running to the left of the popular Brown, who is nearly 30 years older, on Democratic litmus-test issues such as single-payer health care for state residents. Scott Wilson, Washington Post, "Think California politics is on the far-left fringe? Just wait for the next elections.," 3 Feb. 2018 The Arizona senator supported Gang of Eight–style immigration reform, when immigration restriction is becoming a litmus-test issue in the party. Rich Lowry, National Review, "Trump Is the GOP Mainstream," 27 Oct. 2017 Let’s use the following multiple-choice criteria as a good litmus. Jeff Sentell, ajc, "What really matters for the nation’s No. 2 OG Trey Hill about choosing a school," 11 Oct. 2017

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

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First Known Use of litmus

14th century, in the meaning defined at sense 1

History and Etymology for litmus

Middle English litmose, of Scandinavian origin; akin to Old Norse litmosi herbs used in dyeing, from litr color (akin to Old English wlite brightness, appearance) + mosi moss; akin to Old English mōs moss

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Time Traveler for litmus

Time Traveler

The first known use of litmus was in the 14th century

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Last Updated

20 Jun 2020

Cite this Entry

“Litmus.” Dictionary, Merriam-Webster, Accessed 3 Aug. 2020.

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lit·​mus | \ ˈlit-məs How to pronounce litmus (audio) \

Medical Definition of litmus

: a coloring matter from lichens that turns red in acid solutions and blue in alkaline solutions and is used as an acid-base indicator

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More from Merriam-Webster on litmus

Thesaurus: All synonyms and antonyms for litmus

Spanish Central: Translation of litmus

Nglish: Translation of litmus for Spanish Speakers Encyclopedia article about litmus

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