white blood cell

noun

: any of the blood cells that are colorless, lack hemoglobin, contain a nucleus, and include the lymphocytes, monocytes, neutrophils, eosinophils, and basophils

called also leukocyte, white blood corpuscle, white cell

compare red blood cell

Examples of white blood cell in a Sentence

Recent Examples on the Web

Among their many important roles in maintaining human health on a microbiological level, macrophages, which are white blood cells critical to the immune system, seek out pathogens and then engulf and digest them. —New Atlas, 5 Feb. 2025

The woman's urine was also found to contain high levels of white blood cells or pus, blood and nitrites, indicating the presence of a urinary tract infection (UTI), as well as E. coli and Morganella morganii bacteria. —John Yoo and John Shu, Newsweek, 23 Jan. 2025

These immature cells can develop into different types of blood cells, including white blood cells (WBCs), central to immune function.8 Getting sufficient and consistent sleep can help make your body more resistant to disease and infection. —Mark Gurarie, Verywell Health, 9 Jan. 2025

Ultimately, her research led to mast cell activation syndrome, or MCAS, a condition in which mast cells (a type of white blood cell) overreact for reasons that aren’t always clear. —Erica Sloan, SELF, 3 Dec. 2024

Word History

First Known Use

1852, in the meaning defined above

Kids Definition

white blood cell

noun

: a colorless blood cell (as a lymphocyte) that lacks hemoglobin and contains a nucleus

called also leukocyte, white blood corpuscle, white cell, white corpuscle

Medical Definition

white blood cell

noun

: any of the blood cells of the immune system that are colorless, lack hemoglobin, contain a nucleus, and include the lymphocytes, monocytes, neutrophils, eosinophils, and basophils along with their precursors and derivatives (as macrophages) : leukocyte

—abbreviation WBC

called also white blood corpuscle, white cell, white corpuscle

compare red blood cell