[Gram's stain] or Gram stain n [Hans C. J. Gram d. 1938 Dan. physician] (1903) 1: a method for the differential staining of bacteria by treatment with a watery solution of iodine and the iodide of potassium after staining with a triphenylmethane dye (as crystal violet)--called also Gram's method
2: the chemicals used in Gram's stain