litmus test

noun

: a test in which a single factor (such as an attitude, event, or fact) is decisive

Did you know?

Litmus Test Has Scientific Origins

It was in the 14th century that scientists discovered that litmus, a mixture of colored organic compounds obtained from lichen, turns red in acid solutions and blue in alkaline solutions and, thus, can be used as an acid-base indicator. Six centuries later, people began using litmus test figuratively. It can now refer to any single factor that establishes the true character of something or causes something to be assigned to one category or another. Often it refers to something (such as an opinion about a political or moral issue) that can be used to make a judgment about whether someone or something is acceptable or not.

Examples of litmus test in a Sentence

The party is using attitudes about gun control as a litmus test for political candidates.

Recent Examples on the Web

What Happens Next Trump and the rest of his party will likely be looking towards the midterms as a litmus test for how the country is feeling about his governance. —Jordan King, MSNBC Newsweek, 26 Nov. 2025

One litmus test for draft stock is how a player performs against the best of the best, and Smith did not show out against Ohio State (zero pressures), Iowa (one pressure) and Oregon (two pressures and one sack). —Andy Greder, Twin Cities, 26 Nov. 2025

Monday night was a litmus test for the 49ers. —Dieter Kurtenbach, Mercury News, 25 Nov. 2025

The Padres will be an interesting litmus test. —Eben Novy-Williams, Sportico.com, 15 Nov. 2025

Word History

First Known Use

1913, in the meaning defined above

Rhymes for litmus test

• acquiesced
• coalesced
• dispossessed
• manifest
• overdressed
• overstressed
• prepossessed
• reassessed
• reinvest
• repossessed
• unaddressed
• uncompressed

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