macrophage

American  

[mak-ruh-feyj] / ˈmæk rəˌfeɪdʒ /

noun

Cell Biology.

1. a large white blood cell, occurring principally in connective tissue and in the bloodstream, that ingests foreign particles and infectious microorganisms by phagocytosis.

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macrophage British  

/ ˈmækrəʊˌfeɪdʒ, ˌmækrəʊˈfædʒɪk /

noun

1. any large phagocytic cell occurring in the blood, lymph, and connective tissue of vertebrates See also histiocyte

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macrophage Scientific  

/ măk′rə-fāj′ /

1. Any of various large white blood cells that play an essential immunologic role in vertebrates and some lower organisms by eliminating cellular debris and particulate antigens, including bacteria, through phagocytosis. Macrophages develop from circulating monocytes that migrate from the blood into tissues throughout the body, especially the spleen, liver, lymph nodes, lungs, brain, and connective tissue. Macrophages also participate in the immune response by producing and responding to inflammatory cytokines.

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Other Word Forms

• macrophagic adjective

Etymology

Origin of macrophage

From the New Latin word macrophagus, dating back to 1885–90. See macro-, -phage

Example Sentences

By targeting MafB or the biological pathways it regulates, researchers may be able to restore healthy macrophage function and improve tissue health across a range of diseases.

From Science Daily • Mar. 1, 2026

Overall, the findings establish MafB as a central and evolutionarily conserved regulator of macrophage development, identity, and function, offering new insight into how the immune system helps protect and sustain the health of multiple organs.

From Science Daily • Mar. 1, 2026

"The biggest surprise about this was finding that a macrophage has a synaptic-like property that delivers an ion to a muscle fiber to facilitate its repair after an injury," Jankowski says.

From Science Daily • Nov. 24, 2025

"We found the SWI/SNF variants each serve a unique, important purpose in reorganizing chromatin across the genome and enabling macrophage inflammatory responses," says first author Jingwen Liao, a graduate student in Hargreaves' lab.

From Science Daily • Jun. 5, 2024

The other form of amoeboid cell, which Metschnikoff calls the macrophage, has more feeble phagocytic action towards bacteria, and these are rarely found enclosed within them.

From Disease and Its Causes by Councilman, William Thomas