epithelial

American  

[ep-uh-thee-lee-uhl] / ˌɛp əˈθi li əl /

adjective

1. Biology. being or relating to an epithelium, any tissue that lines a cavity or covers a surface in an animal or plant.

   Cheek epithelial cells are often studied in school labs as they are easily obtained through a mouth rinse or swab.

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Other Word Forms

• interepithelial adjective
• nonepithelial adjective
• subepithelial adjective
• unepithelial adjective

Etymology

Origin of epithelial

First recorded in 1935–40; epitheli(um) ( def. ) + -al ¹ ( def. )

Example Sentences

"They're able to absorb nutrients better. They have much less inflammation. When irritated or injured, their epithelial lining is able to regenerate and heal much faster."

From Science Daily • Jan. 3, 2026

These include hormonal cancers like uterine cancer, as well as epithelial cancers, such as some types of liver cancer.

From Salon • Jan. 24, 2025

A preprint out this week indicates currently circulating clade 2.3.4.4b viruses are better at binding to human epithelial cells in the airways than previous versions of H5N1.

From Science Magazine • Dec. 5, 2024

Additionally, epithelial cells are found in many body systems, highlighting the possibility that these findings can translate to other organs.

From Science Daily • Nov. 20, 2024

There were fertile red meadows of epithelial tissue to catch and coddle a cancer cell.

From "Catch-22" by Joseph Heller