• Webster's Revised Unabridged Dictionary
    • n Orcin (Chem) A colorless crystalline substance, C6H3.CH3.(OH)2, which is obtained from certain lichens (Roccella Lecanora, etc.), also from extract of aloes, and artificially from certain derivatives of toluene. It changes readily into orcein.
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Century Dictionary and Cyclopedia
    • n orcin A peculiar coloring matter, represented by the formula C7H6(OH2), obtained from the orchella-weed and other lichens. It crystallizes in colorless prisms, and its taste is sweet and nauseous. When dissolved in ammonia it gradually acquires a deep blood-red color, and there is formed on exposure to air a new substance called orcein, which contains nitrogen as an essential element, and may be a mixture of several different compounds. On the addition of acetic acid orcein is precipitated as a brownish red powder. Also called orcinol.
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Webster's Revised Unabridged Dictionary
Etymology uncertain: cf. F. orcine,