From Longman Dictionary of Contemporary Englishlitmus testˈlitmus ˌtest noun [singular] 1 CLEAR/EASY TO UNDERSTANDone detail that is examined in order to help you make a decision about how suitable or acceptable someone or something islitmus test of/for The mayoral election is regarded as the litmus test for the integrity of the electoral process.2 HCa test using litmus paper
Examples from the Corpus
litmus test• The case of travellers is something of a litmus test.• For example, in his chemistry exam John wrote for the first three answers blank, ether and litmus test.• What clearer laboratory or litmus test could there be to show that our methods are genuinely additional?• He instituted a stringent litmus test on doctrinal matters.• Personal loyalty seems to be the litmus test for the mayor's new appointees.• Comparison is the only true litmus test of objectivity.litmus test of/for• Forbes, meanwhile, has made winning Arizona his litmus test for capturing the nomination.• Comparison is the only true litmus test of objectivity. 