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Synonyms

litmus test

American  

noun

  1. Chemistry. the use of litmus paper or solution to test the acidity or alkalinity of a solution.

  2. a crucial and revealing test in which there is one decisive factor.


litmus test British  

noun

  1. a test to establish the acidity or alkalinity of a mixture

  2. a critical indication of future success or failure

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of litmus test

First recorded in 1955–60; so called from chemical tests in which litmus or litmus paper is an indicator

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

An exciting brand of rugby brought positive vibes back and supplied victories over France, Italy and Ireland this summer, but the real litmus test comes in the Tests against South Africa.

From BBC Aug. 17, 2026

Josh Adams believes Wales' daunting Nations Championship fixture against South Africa will be the litmus test of their progress under Steve Tandy.

From BBC Jul. 13, 2026

The round-of-16 game at Lumen Field was the ultimate litmus test for U.S.

From The Wall Street Journal Jul. 7, 2026

They also provide a valuable litmus test for contemporary romance.

From Salon Mar. 19, 2026

If unity is indeed the litmus test of human progress, neither history nor Heaven will readily forgive those who choose deliberately to raise their hands against it.

From One Common Faith by Baha'i International Community

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