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

Chesney’s mental training ultimately serves as a litmus test in discovering who is cut from a different cloth. — Connor Dullinger, Los Angeles Times, 7 Aug. 2026

With three preseason games and two joint practices ahead in the coming weeks, the Cowboys will get a few litmus tests before hitting the field in Week 1 against the New York Giants. — Nick Harris, Fort Worth Star-Telegram, 7 Aug. 2026

Add in the race and religion factors animating the race, and Tuesday’s primary in Michigan could lay bare which litmus tests are likely to shape the 2028 presidential contest. — Philip Elliott, Time, 3 Aug. 2026

Through a more critical lens, many in Hollywood will treat its box office result as a litmus test for Marvel’s health for 2026 and beyond. — Jack Dunn, Variety, 30 July 2026

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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