'Methylene blue' definitions:

Definition of 'methylene blue'

From: WordNet
noun
A dark green dye used as a stain, an antiseptic, a chemical indicator, and an antidote in cyanide poisoning [syn: methylene blue, methylthionine chloride]

Definition of 'Methylene blue'

From: GCIDE
  • Methylene \Meth"yl*ene\, n. [F. m['e]thyl[`e]ne, from Gr. ? wine + ? wood; -- a word coined to correspond to the name wood spirit.] (Chem.) A divalent hydrocarbon radical, -CH2-, not known in the free state, but regarded as an essential residue and component of certain derivatives of methane; as, methylene bromide, CH2Br2; -- formerly called also methene. [1913 Webster]
  • Methylene blue (Chem.), an artificial dyestuff consisting of a complex sulphur derivative of diphenyl amine; -- called also pure blue. [1913 Webster]