Definition of "litmus" []

• A water-soluble blue powder derived from certain lichens that changes to red with increasing acidity and to blue with increasing basicity. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "‡ The term litmus is often used to refer to a general and simple test: “Your vote on this issue is a litmus test of your political philosophy."
• "He said Angola had reached the point when soldiers would be quartered in camps and demobilized, which he called the litmus test for peace."
• "This is what Israeli Democracy Looks Like '; yahooBuzzArticleSummary =' Article: Freedom of the press is often called the litmus test of democracy."