Gram's method

American  

[gramz] / græmz /

noun

(sometimes lowercase)

1. a method of staining and distinguishing bacteria, in which a fixed bacterial smear is stained with crystal violet, treated with Gram's solution, decolorized with alcohol, counterstained with safranine, and washed with water.

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Gram's method British  

noun

1. bacteriol a staining technique used to classify bacteria, based on their ability to retain or lose a violet colour, produced by crystal violet and iodine, after treatment with a decolorizing agent See also Gram-negative Gram-positive

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Etymology

Origin of Gram's method

Named after Hans C. J. Gram (1853–1938), Danish bacteriologist

Example Sentences

Young individuals are stained by Gram's method; older individuals are, however, Gram negative.

From The Bacillus of Long Life a manual of the preparation and souring of milk for dietary purposes, together with and historical account of the use of fermente by Douglas, Loudon

Glanders is due to the action of a specific bacterium, the bacillus mallei, which resembles the tubercle bacillus, save that it is somewhat shorter and broader, and does not stain by Gram's method.

From Manual of Surgery Volume First: General Surgery. Sixth Edition. by Thomson, Alexis

Stain carbolic methylene-blue, carbolic fuchsin, and Gram's method.

From The Elements of Bacteriological Technique A Laboratory Guide for Medical, Dental, and Technical Students. Second Edition Rewritten and Enlarged. by Eyre, J. W. H. (John William Henry)

Stain: Gram's method coloured with aqueous fuchsine afterwards.

From The Bacillus of Long Life a manual of the preparation and souring of milk for dietary purposes, together with and historical account of the use of fermente by Douglas, Loudon

In Gram's method, however, only some bacteria retain the stain, while others lose it.

From Encyclopaedia Britannica, 11th Edition, Volume 3, Part 1, Slice 2 "Baconthorpe" to "Bankruptcy" by Various