endothelium
noun
en·do·the·li·um
ˌen-də-ˈthē-lē-əm 
-dō-
plural endothelia
ˌen-də-ˈthē-lē-ə
-dō-
1
: an epithelium of mesodermal origin composed of a single layer of thin flattened cells that lines internal body cavities and the lumens of vessels
2
: the inner layer of the seed coat of some plants
Examples of endothelium in a Sentence
Recent Examples on the Web
In a healthy person, the endothelium helps prevent blood clots by producing chemicals that tweak the vascular system to keep it running.
—
Kff Health News, San Diego Union-Tribune, 10 June 2025
In a healthy person, the endothelium helps prevent blood clots by producing chemicals that keep the vascular system running.
—Jackie Fortiér, NPR, 30 May 2025
The virus that causes covid can affect the vascular endothelium — specialized cells that line blood vessels and help with blood flow, Rasmussen said.
—Kff Health News, Oc Register, 2 June 2025
Healthy endothelium cells also play a role in local cell growth and help prevent blood clotting.
—Sandee Lamotte, CNN Money, 28 May 2025
Aging and menopause contribute to the dysfunction of the endothelium (cells of blood vessels).
—Merve Ceylan, Health, 27 Dec. 2024
These complexes establish productive cellular infections in macrophages that result in the release of high concentrations of toxic NS1, a viral protein that damages cells' endothelium and produces dengue shock syndrome.
—Scientific American, 1 Jan. 2024
The corneal endothelium is a thin layer of cells that forms the inner lining of the cornea.
—William A. Haseltine, Forbes, 17 Feb. 2024
The innermost layer is known as the endothelial layer; exercise has been shown to influence the activity of the endothelium.
—Amber Sayer, Health, 25 Sep. 2023
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Kff Health News, San Diego Union-Tribune, 10 June 2025
In a healthy person, the endothelium helps prevent blood clots by producing chemicals that keep the vascular system running.
—Jackie Fortiér, NPR, 30 May 2025
The virus that causes covid can affect the vascular endothelium — specialized cells that line blood vessels and help with blood flow, Rasmussen said.
—Kff Health News, Oc Register, 2 June 2025
Healthy endothelium cells also play a role in local cell growth and help prevent blood clotting.
—Sandee Lamotte, CNN Money, 28 May 2025
Aging and menopause contribute to the dysfunction of the endothelium (cells of blood vessels).
—Merve Ceylan, Health, 27 Dec. 2024
These complexes establish productive cellular infections in macrophages that result in the release of high concentrations of toxic NS1, a viral protein that damages cells' endothelium and produces dengue shock syndrome.
—Scientific American, 1 Jan. 2024
The corneal endothelium is a thin layer of cells that forms the inner lining of the cornea.
—William A. Haseltine, Forbes, 17 Feb. 2024
The innermost layer is known as the endothelial layer; exercise has been shown to influence the activity of the endothelium.
—Amber Sayer, Health, 25 Sep. 2023
Cite this Entry
“Endothelium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/endothelium. Accessed 30 Jun. 2025.
Copy CitationMedical Definition
endothelium
noun
en·do·the·li·um
ˌen-də-ˈthē-lē-əm
plural endothelia
-lē-ə
: an epithelium of mesoblastic origin composed of a single layer of thin flattened cells that lines internal body cavities (as the serous cavities or the interior of the heart)
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