Litmus Test (Noun)
Meaning 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.
Classification
Nouns denoting substances.
Synonyms
Hypernyms
Meaning 2
A test that relies on a single indicator; "her litmus test for good breeding is whether you split infinitives".
Classification
Nouns denoting communicative processes and contents.