DICT.TW Dictionary Taiwan

 Lit·mus n.  Chem. A dyestuff extracted from certain lichens (Roccella tinctoria, Lecanora tartarea, etc.), as a blue amorphous mass which consists of a compound of the alkaline carbonates with certain coloring matters related to orcin and orcein.
 Note: ☞ Litmus is used as a dye, and being turned red by acids and restored to its blue color by alkalies, is a common indicator or test for acidity and alkalinity.
 Litmus paper Chem., unsized paper saturated with blue or red litmus, -- used in testing for acids or alkalies.
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 Cud·bear n.
 1. A powder of a violet red color, difficult to moisten with water, used for making violet or purple dye. It is prepared from certain species of lichen, especially Lecanora tartarea.
 2. Bot. A lichen (Lecanora tartarea), from which the powder is obtained.
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