epithelium

noun

ep·​i·​the·​li·​um ˌe-pə-ˈthē-lē-əm How to pronounce epithelium (audio)
plural epithelia ˌe-pə-ˈthē-lē-ə How to pronounce epithelium (audio)
1
: a membranous cellular tissue that covers a free surface or lines a tube or cavity of an animal body and serves especially to enclose and protect the other parts of the body, to produce secretions and excretions, and to function in assimilation
2
: a usually thin layer of parenchyma that lines a cavity or tube of a plant

Examples of epithelium 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.
Most of the body's immune cells are found in the connective tissues of the small intestines, just beneath the epithelium. Mark Gurarie, Health, 6 Nov. 2024 To their surprise, the cells self-assembled into a network of layers that resembled the retina pigment epithelium and its vasculature. William A. Haseltine, Forbes, 24 Jan. 2023 In the nose, expression is seen in both the respiratory epithelium (RE) and the olfactory sensory epithelium (OSE) but in much higher levels in the OSE. Leslie Kay, Scientific American, 13 June 2020 So might anatomical responses to those changes, such as the effect of colder or drier air on mucous membranes and the epithelium of the respiratory tract. WIRED, 2 Oct. 2023 See all Example Sentences for epithelium 

Word History

Etymology

New Latin, from epi- + Greek thēlē nipple — more at feminine

First Known Use

1748, in the meaning defined at sense 1

Time Traveler
The first known use of epithelium was in 1748

Dictionary Entries Near epithelium

Cite this Entry

“Epithelium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/epithelium. Accessed 22 Dec. 2024.

Kids Definition

epithelium

noun
ep·​i·​the·​li·​um ˌep-ə-ˈthē-lē-əm How to pronounce epithelium (audio)
plural epithelia -lē-ə How to pronounce epithelium (audio)
1
: a tissue like a membrane that is made up of cells and covers a free surface or lines a tube or cavity of an animal body
2
: a usually thin layer of cells of a plant that is part of the parenchyma and lines a cavity or tube
epithelial
-lē-əl
adjective

Medical Definition

epithelium

noun
ep·​i·​the·​li·​um ˌep-ə-ˈthē-lē-əm How to pronounce epithelium (audio)
plural epithelia -lē-ə How to pronounce epithelium (audio)
: a membranous cellular tissue that covers a free surface or lines a tube or cavity of an animal body and serves especially to enclose and protect the other parts of the body, to produce secretions and excretions, and to function in assimilation

More from Merriam-Webster on epithelium

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