litmus paper

noun

1. a strip of paper impregnated with litmus, used as a chemical indicator.

Word History and Origins

Origin of litmus paper¹

First recorded in 1795–1805

Example Sentences

The best way to confirm that the solution is neutralized is with litmus paper.

From Seattle Times

Watson recalls one telling advertising campaign: posters printed on litmus paper that said: “When acid rain is falling, you should see red” – offering a vivid illustration of the problem.

From The Guardian

Testing kits come in all shapes and sizes, but when working with kids, it’s best to use a simple litmus paper test.

From Seattle Times

You’ll put some garden soil and water in a tiny vial, shake it up, and dunk litmus paper to check the pH.

From Seattle Times

"I don't demand that a theory correspond to reality because I don't know what it is. Reality is not a quality you can test with litmus paper. All I'm concerned with is that the theory should predict the results of measurements."

From Salon