| slovo | definícia |
roccella
(encz) | roccella, n: |
Roccella
(gcide) | 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
(wn) | roccella
n 1: a source of the dye archil and of litmus [syn: roccella,
Roccella tinctoria] |
| | podobné slovo | definícia |
roccella
(encz) | roccella, n: |
Roccella tinctoria
(gcide) | Litmus \Lit"mus\, n. [D. lakmoes; lak lacker + moes a thick
preparation of fruit, pap, prob. akin to E. meat: cf. G.
lackmus. See Lac a resinous substance.] (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.
[1913 Webster]
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.
[1913 Webster]
Litmus paper (Chem.), unsized paper saturated with blue or
red litmus, -- used in testing for acids or alkalies.
[1913 Webster]Roccellic \Roc*cel"lic\, a. [F. roccellique, fr. roccelle
archil, It. & NL. roccella, fr. It. rocca a rock, because
archil grows on rock.] (Chem.)
Pertaining to, or designating, a dibasic acid of the oxalic
series found in archil (Roccella tinctoria, etc.), and
other lichens, and extracted as a white crystalline substance
C17H32O4.
[1913 Webster]Archil \Ar"chil\ (?; 277), n. [OF. orchel, orcheil, It. orcella,
oricello, or OSp. orchillo. Cf. Orchil.]
1. A violet dye obtained from several species of lichen
(Roccella tinctoria, etc.), which grow on maritime rocks
in the Canary and Cape Verd Islands, etc. --Tomlinson.
[1913 Webster]
2. The plant from which the dye is obtained. [Written also
orchal and orchil.]
[1913 Webster] |
family roccellaceae
(wn) | family Roccellaceae
n 1: a fungus family of division Lichenes [syn: Roccellaceae,
family Roccellaceae] |
genus roccella
(wn) | genus Roccella
n 1: chiefly fruticose maritime rock-inhabiting lichens |
roccella
(wn) | roccella
n 1: a source of the dye archil and of litmus [syn: roccella,
Roccella tinctoria] |
roccella tinctoria
(wn) | Roccella tinctoria
n 1: a source of the dye archil and of litmus [syn: roccella,
Roccella tinctoria] |
roccellaceae
(wn) | Roccellaceae
n 1: a fungus family of division Lichenes [syn: Roccellaceae,
family Roccellaceae] |
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