What does granulocyte mean?
A granulocyte is one of several types of white blood cell that contains visible granules in its cytoplasm. In humans, the principal granulocytes are neutrophils, eosinophils and basophils, which differ in the color and contents of their granules. These cells are key components of innate immunity: neutrophils chiefly counter infection and clear debris, eosinophils contribute to parasite defense and allergic responses, and basophils release histamine and other mediators involved in inflammation and hypersensitivity. The term is most common in hematology, immunology and clinical laboratory reports, where granulocyte counts are often used to assess neutrophil production and immune status. Although “granulocyte” sometimes evokes a neutrophil in clinical shorthand, it is not synonymous with “white blood cell” as a whole. Instead, it names a recognizable cellular family whose granules make them microscopically distinct. Understanding the term helps distinguish these specialized defenders from other blood cells and explains why clinicians discuss granulocyte production, counts and deficiencies.
nounA granulocyte is a white blood cell containing conspicuous granules in its cytoplasm. In humans, the principal granulocytes are neutrophils, eosinophils and basophils.
- A white blood cell whose cytoplasm contains visible granules, especially a neutrophil, eosinophil or basophil in humans.
"The blood film showed an elevated number of granulocytes, consistent with an acute bacterial infection."
"The blood film showed an elevated number of granulocytes, consistent with an acute bacterial infection."
"Granulocyte colony-stimulating factor is used clinically to support neutrophil production."
The standard plural adds -s and is used when referring to several granulocytes or to granulocytes as a group.
"Researchers examined the granulocytes in each blood sample."
The name is a visual clue: under a microscope, a granulocyte’s cytoplasm is speckled with tiny granules.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does granulocyte come from?
Granulocyte was formed in modern English from the Latin-derived stem granul-, associated with granum, meaning “grain,” together with the combining form -cyte, from Greek kytos, meaning “cell.” The resulting name refers directly to the granular appearance of the cell under a microscope. It belongs to a broader family of English words associated with grain or granules, including granule, granular, granulation and granuloma.
Related word forms
How granulocyte is actually used
This is primarily a specialist term in hematology, immunology and clinical laboratory medicine. It denotes a category of white blood cell rather than all white blood cells.
Easily confused with granulocyte
A lymphocyte is a white blood cell without the conspicuous cytoplasmic granules characteristic of a granulocyte.
A granuloma is an area of inflamed tissue, not a granulocyte, which is an individual white blood cell.