litmus paper


: unsized paper colored with litmus and used as an indicator

Example Sentences

Recent Examples on the Web 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

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

Word History

First Known Use

1803, in the meaning defined above

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

Dictionary Entries Near litmus paper

Cite this Entry

“Litmus paper.” Dictionary, Merriam-Webster, Accessed 4 Dec. 2022.

Kids Definition

litmus paper


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

Medical Definition

litmus paper


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

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