litmus test

Từ điển Oxford Learners Wordfinder Dictionary

noun

1. a coloring material (obtained from lichens) that turns red in acid solutions and blue in alkaline solutions;
used as a very rough acid-base indicator
• Syn:
litmus
• Hypernyms:
acid-base indicator
• Substance Holonyms:
litmus paper
2. a test that relies on a single indicator
- her litmus test for good breeding is whether you split infinitives
• Hypernyms:
examination, exam, test