What is Romanowsky stain?

Romanowsky staining, also known as Romanowsky–Giemsa staining, is a prototypical staining technique that was the forerunner of several distinct but similar stains widely used in hematology and cytopathology. Romanowsky-type stains are used to differentiate cells for microscopic examination in pathological specimens, especially blood and bone marrow films, and to detect parasites such as malaria within the blood. Stains that are related to or derived from the Romanowsky-type stains include Giemsa, Jenner, Wright, Field, May–Grünwald and Leishman stains. The staining technique is named after the Russian physician Dmitri Leonidovich Romanowsky , who was one of the first to recognize its potential for use as a blood stain.