eosinophil

1 of 2

adjective

eo·​sin·​o·​phil ˌē-ə-ˈsi-nə-ˌfil How to pronounce eosinophil (audio)

eosinophil

2 of 2

noun

: a granulocyte readily stained by eosin that is present at sites of allergic reactions and parasitic infections

Examples of eosinophil in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Adjective
In addition to eosinophil counts, the researchers measured white blood cells, inflammation markers, pain intensity, complications and comorbidities (conditions such as asthma, migraine, fibromyalgia, and rheumatoid arthritis). New Atlas, 13 Oct. 2025 The typical complete blood count panel includes an eosinophil count, so most people already have that information in their medical records. Claire Bugos, Verywell Health, 29 Apr. 2025 These findings suggest that Dupixent may be a good add-on therapy for people who have high eosinophil levels that suggest inflammation in their lungs and who don’t get enough symptom relief from COPD inhalers, says Hanania. Lisa Rapaport, EverydayHealth.com, 27 Sep. 2024 The research has also suggested a role for a certain type of vitamin D (gamma-tocopherol) that appears to calm the eosinophil response to pollution. Linda Carroll, TIME, 30 May 2024 Elevated eosinophils can also be seen in patients with asthma, and this patient had a history of asthma, but even then eosinophil counts are rarely this high. Lisa Sanders, New York Times, 16 May 2018
Noun
Patients with and without eosinophilia were compared, with eosinophilia defined as ≥350 eosinophils per microliter of blood – a mild threshold, slightly lower than the standard 500 eosinophils per microliter. New Atlas, 13 Oct. 2025 Struggles With a Rare Condition Parker lived with eosinophilic esophagitis (EoE), a chronic allergic condition where white blood cells called eosinophils build up in the esophagus. Lucy Notarantonio, MSNBC Newsweek, 5 Sep. 2025 Blood work showed the presence of eosinophils — a type of white blood cell that fights parasitic infections. Cara Lynn Shultz, People.com, 2 July 2025 One feature stood out: The man had developed elevated levels of eosinophils, white blood cells that can increase for various reasons—including parasitic infections. ArsTechnica, 20 June 2025 It is only approved for people with high levels of eosinophils, a type of immune cell that contributes to inflammation. Claire Bugos, Verywell Health, 29 Apr. 2025 Blood tests showed elevated eosinophils, which can be a sign of a parasitic infection, among other things. Ars Technica, 11 Mar. 2025

Word History

First Known Use

Adjective

circa 1882, in the meaning defined above

Noun

circa 1900, in the meaning defined above

Time Traveler
The first known use of eosinophil was circa 1882

Browse Nearby Words

Cite this Entry

“Eosinophil.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/eosinophil. Accessed 17 Oct. 2025.

Kids Definition

eosinophil

noun
eo·​sin·​o·​phil
ˌē-ə-ˈsin-ə-ˌfil
: a white blood cell with a granule-containing cytoplasm that is found in the body at sites of allergic reactions and parasitic infections

Medical Definition

eosinophil

1 of 2 adjective
eo·​sin·​o·​phil ˌē-ə-ˈsin-ə-ˌfil How to pronounce eosinophil (audio)
variants also eosinophile

eosinophil

2 of 2 noun
variants also eosinophile
: a white blood cell or other granulocyte with cytoplasmic inclusions readily stained by eosin

More from Merriam-Webster on eosinophil

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!