litmus paper

noun

: unsized paper colored with litmus and used as an indicator

Examples of litmus paper in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Liquid samples can be tested with detector paper, which is similar to a large piece of litmus paper. — Popular Mechanics Editors, Popular Mechanics, 7 Aug. 2018

Word History

First Known Use

1803, in the meaning defined above

Time Traveler
The first known use of litmus paper was in 1803

Rhymes for litmus paper

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Browse Nearby Words

litmus milk
litmus paper
litmus test
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Cite this Entry

“Litmus paper.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/litmus%20paper. Accessed 4 Jul. 2026.

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Kids Definition

litmus paper

noun
lit·​mus paper
ˈlit-məs-
: paper treated with coloring matter that turns red in acid solutions and blue in alkaline solutions

Medical Definition

litmus paper

noun
: paper colored with litmus and used as an acid-base indicator

More from Merriam-Webster on litmus paper

Nglish: Translation of litmus paper for Spanish Speakers

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