litmus
A dyestuff extracted from certain lichens, that changes color when exposed to pH levels greater than or less than certain critical levels.
Other meanings
A simple test of acidity in a liquid using litmus, usually in the form of litmus paper.
A simple test of any attribute; a litmus test.
Synonyms
- indicator
Related words
- azolitmin
- litmus milk
- litmus paper
- litmus test
Word history
From Old Norse "litmosi" (moss used for dyeing).
Where this comes from
This definition is adapted from “litmus” on Wiktionary, by its contributors, published under CC BY-SA 4.0. This page is published under the same licence.