What does macrocyte mean?
A macrocyte is a red blood cell that is larger than normal. The term is used mainly in hematology, where the size and number of red blood cells can help clinicians identify and investigate anemia. Macrocytes are commonly associated with megaloblastic anemia due to vitamin B12 or folate deficiency, but they may also occur in liver disease, alcohol-related changes, certain bone-marrow disorders, and some medications. A macrocyte describes an individual enlarged cell, whereas macrocytosis denotes the presence of an increased number or proportion of these cells. Laboratory findings may also use the related adjective macrocytic, as in “macrocytic anemia,” while macrocytosis names the morphological condition itself. Although blood-cell size is a useful diagnostic clue, it is interpreted alongside other blood counts, symptoms, and clinical findings rather than in isolation.
nounA red blood cell that is larger than normal, typically measuring more than about 14 micrometres in diameter. Macrocytes may occur in several types of anemia and are also associated with some nutritional, liver, and bone-marrow disorders.
- A red blood cell that is larger than normal.
"The blood film showed numerous macrocytes, prompting the clinician to investigate vitamin B12 and folate deficiency."
"Peripheral blood smear revealed macrocytes with an average corpuscular volume above the expected range."
"Macrocytes can be seen in megaloblastic anemia caused by vitamin B12 deficiency."
The plural is commonly used when describing multiple enlarged red blood cells found in a blood film or count.
"Numerous macrocytes were visible on the peripheral blood smear."
A macrocyte is literally a large cell: its name combines roots meaning “large” and “cell,” a reminder that blood-cell size can provide important diagnostic clues.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does macrocyte come from?
The word combines the combining form macro-, from Greek makros meaning “large,” with -cyte, from Greek kytos meaning “cell.” Together, the elements literally mean “large cell,” accurately describing an abnormally large red blood cell. The same Greek roots appear in cognates such as cytology, cytoplasm, leukocyte, and macrophage.
Related word forms
How macrocyte is actually used
This is primarily a medical and hematological term used in blood-film reports and clinical discussion. It denotes the individual cell; macrocytosis refers to an increased prevalence of such cells.
Easily confused with macrocyte
A macrocyte is an individual large red blood cell, whereas macrocytosis is the condition of having an increased number or proportion of large red blood cells.
Megalocyte is a less common synonym for macrocyte and may also emphasize an especially large red blood cell.