What is another word for the acid test?
Pronunciation: [ðɪ ˈasɪd tˈɛst] (IPA) 
"The acid test" is a phrase that refers to a test or trial that is exceptionally rigorous and exacting. One synonym for this expression is "the litmus test," which comes from the litmus paper that is used to test the pH of solutions. Another synonym is "the ultimate test," which suggests a final, decisive examination that will determine the truth or validity of something. "The acid test" can also be expressed as "the acid trial" or "the gold standard," which imply a level of difficulty or quality that is necessary for something to be deemed successful. Regardless of the wording used, all of these synonyms convey the importance and rigor of this type of test.
