litmus

名词 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
   同义词：litmus test

1. Litmus paper can be used as an indicator of the presence of acid in a solution.
   石蕊试纸可用以测试溶液是否含酸。

lit.mus

n.（名词）
A water-soluble blue powder derived from certain lichens that changes to red with increasing acidity and to blue with increasing basicity.
石蕊：取自地衣的一种可溶于水的蓝色粉末，可随酸性增大而变红，随碱度增大而变蓝

来源：
Middle English litmose
中古英语 litmose
[of Scandinavian origin] ; akin to Old Norse litmosi [dyer`s herbs]
[源于斯堪的纳维亚语] ；类似于 古斯堪的纳维亚语 litmosi [蓝靛]
litr [color, dye]
litr [着色、染色]
mosi [bog, moss]
mosi [沼泽，苔]