polycythemia

noun

poly·​cy·​the·​mia ˌpä-lē-(ˌ)sī-ˈthē-mē-ə How to pronounce polycythemia (audio)
: a condition marked by an abnormal increase in the number of circulating red blood cells
specifically : polycythemia vera
polycythemic adjective

Word History

Etymology

borrowed from German Polycythaemie, from poly- poly- + cyt- cyt- + -haemie -hemia

First Known Use

circa 1857, in the meaning defined above

Time Traveler
The first known use of polycythemia was circa 1857

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Cite this Entry

“Polycythemia.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/polycythemia. Accessed 1 Mar. 2025.

Medical Definition

polycythemia

noun
poly·​cy·​the·​mia
variants or chiefly British polycythaemia
: a condition marked by an abnormal increase in the number of circulating red blood cells
especially : polycythemia vera compare erythrocytosis

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