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 it 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

The partnership goes beyond the AI chip leader’s conventional Western collaborations and may serve as a litmus test for future U.S. export policies with nations that keep close ties with both Washington and China. —Chris Eudaily,kristina Partsinevelos, CNBC, 14 May 2025

Multiple states are gearing up for competitive gubernatorial elections in 2026, which will offer a litmus test on voter sentiment. —Alexis Simendinger, The Hill, 6 May 2025

American leaders had framed participation in the Revolution as a litmus test of masculinity, patriotism, and commitment to liberty among American men. —Time, 5 May 2025

Travis Hunter test If the Patriots truly take a best-player-available approach to the draft, the No. 4 pick could offer an immediate litmus test. —Andrew Callahan, Boston Herald, 19 Mar. 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