Word Study
endothelium
CIDE DICTIONARY
endothelium, n. [NL., fr. Gr. 'e`ndon within + nipple.].
The thin epithelium lining the blood vessels, lymphatics, and serous cavities. See Epithelium. [1913 Webster]
OXFORD DICTIONARY
endothelium, n. Anat. a layer of cells lining the blood-vessels, heart, and lymphatic vessels.
Etymology
ENDO- + Gk thele teat
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