Skip to main content
Gram method

Gram method

4.4
A lab method to tell types of bacteria by staining them to see if they keep a purple dye
  • noun
  • /ɡræm ˈmɛθəd/
  • Specialized
translation icon : método de Gram
  • After using the Gram method, the microbiologist determined the bacteria were Gram-negative.

Examples

  • The Gram method is essential for identifying bacterial species in clinical laboratories.

  • Medical students must learn the proper steps of the Gram method during their training.

  • The Gram method is essential in microbiology.

  • Did you learn about the Gram method in class?

  • The Gram method allows scientists to distinguish between Gram-positive and Gram-negative bacteria.

  • In the laboratory, we frequently use the Gram method to classify unknown bacterial samples.

  • Understanding the Gram method is fundamental for microbiology students studying bacterial classification.

Synonyms

Gram stain
vsGram method
  • Specialized
1 5.1

A lab test that uses dyes and a microscope to show if bacteria keep a purple colour

is described more generally without explicitly naming a laboratory setting
Gram's stain
vsGram method
  • Specialized
1 4.8

A lab method that uses dye to show whether bacteria keep or lose the dye

specifies gentian violet and other specific reagents for classification
Gram's method
vsGram method
  • Specialized
4.4

A way to stain bacteria with purple dye to tell them apart

focuses on classifying bacteria by staining without stressing the field of use
Gram's procedure
vsGram method
  • Specialized
6.0

A lab method that stains bacteria to show if they have thick or thin cell walls

emphasizes staining with gentian violet and other reagents rather than structure

Surface Forms

Gram method singular
Gram methods plural

Morphology

Gram + method

The phrase names a specific scientific staining technique and the element 'Gram' is an eponym/proper name rather than a compositional lexical item whose meaning a learner could infer. Knowing 'method' alone does not reveal the bacteriology/staining sense, so a typical B1 learner would not be able to derive the MWE's meaning from its parts.

Etymology

Gram method is named after a scientist, Hans Christian Gram, who used a purple dye to color bacteria. Some bacteria kept the purple color and others did not, so the color test became a simple way to 'tell them apart', and that is why the Gram method means this test today.