Simple Definition of litmus test
: something (such as an opinion about a political or moral issue) that is used to make a judgment about whether someone or something is acceptable
Full Definition of litmus test
: a test in which a single factor (as an attitude, event, or fact) is decisive
Examples of litmus test in a sentence
The party is using attitudes about gun control as a litmus test for political candidates.
Did You Know?
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.
First Known Use of litmus test
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