名詞 litmus:

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
   同義詞：litmus test

1. Litmus paper can be used as an indicator of the presence of acid in a solution.
   石蕊試紙可用以測試溶液是否含酸。

lit.mus

n.（名詞）
A water-soluble blue powder derived from certain lichens that changes to red with increasing acidity and to blue with increasing basicity.
石蕊：取自地衣的一種可溶于水的藍色粉末，可隨酸性增大而變紅，隨堿度增大而變藍

來源：
Middle English litmose
中古英語 litmose
[of Scandinavian origin] ; akin to Old Norse litmosi [dyer`s herbs]
[源于斯堪的納維亞語] ；類似于 古斯堪的納維亞語 litmosi [藍靛]
litr [color, dye]
litr [著色、染色]
mosi [bog, moss]
mosi [沼澤，苔]