roccella

2 definitions found

roccella - Collaborative International Dictionary of English v.0.48 :

  Orcin \Or"cin\, n. [Etymology uncertain: cf. F. orcine.] (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.
     [1913 Webster]

roccella - WordNet (r) 2.1 (2005) :

  roccella
      n 1: a source of the dye archil and of litmus [syn: roccella,
           Roccella tinctoria]