litmus

noun

lit·​mus ˈlit-məs How to pronounce litmus (audio)
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
These examples are automatically compiled from online sources to illustrate current usage. Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
Alpert maintains that his litmus for music has remained the same throughout the decades. Gary Graff, Billboard, 26 Sep. 2024 Looking into next year, Fallout will be an early litmus. Will Bedingfield, WIRED, 28 Dec. 2023 Rahmani pointed to Smollett’s forfeiture of his $10,000 bond as a litmus not only for punishment but acceptance of the Foxx agreement. Fox News, 17 Mar. 2022 The 2023 roster will feature two players who could represent litmus tests for how aggressively the Sox will approach such extensions: righthander Brayan Bello and first baseman Triston Casas. Alex Speier, BostonGlobe.com, 27 Jan. 2023 See all Example Sentences for litmus 

Word History

Etymology

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

First Known Use

14th century, in the meaning defined at sense 1

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

Dictionary Entries Near litmus

Cite this Entry

“Litmus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/litmus. Accessed 17 Nov. 2024.

Medical Definition

litmus

noun
lit·​mus ˈlit-məs How to pronounce litmus (audio)
: a coloring matter from lichens that turns red in acid solutions and blue in alkaline solutions and is used as an acid-base indicator

More from Merriam-Webster on litmus

Last Updated: - Updated example sentences
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