methylene blue

American  

noun

Chemistry, Pharmacology.

1. a dark-green, crystalline compound, C 1 6 H 1 8 ClN 3 S, that dissolves in water to form a deep-blue solution: used chiefly as a dye, as a bacteriological and biological stain, and as an antidote for cyanide poisoning.

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methylene blue British  

noun

1. Also called: methylthionine chloride.  a dark-green crystalline compound forming a blue aqueous solution, used as a mild antiseptic and biological stain. Formula: C 16 H 18 N 3 SCl.3H 2 O

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methylene blue Scientific  

1. A basic dye that forms a deep blue solution when dissolved in water. It is used as an antidote for cyanide poisoning and as a bacteriological stain. Chemical formula: C ₁₆ H ₁₈ N ₃ SCl.

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Etymology

Origin of methylene blue

First recorded in 1885–90

Example Sentences

Methylene Blue, 1-1/2�lb. extract of logwood, and 4�lb. extract of fustic, working at the boil for two hours.

From The Dyeing of Woollen Fabrics by Beech, Franklin

Methyl Violet, Auramine and Methylene Blue, because of their special physiological action.

From Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 8 "Dubner" to "Dyeing" by Various

Methylene Blue and 1�lb. fustic extract, working at the boil.

From The Dyeing of Woollen Fabrics by Beech, Franklin