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

The scientists also found significant changes in epithelial cells that line the lungs and the tiny air sacs responsible for breathing.

From Science Daily • Mar. 13, 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

Using single-cell sequencing and spatial mapping, the researchers specifically investigated breast epithelial cells.

From Science Daily • Nov. 20, 2024

Rather, the article said, it was “a very aggressive adenocarcinoma of the cervix,” meaning it originated from glandular tissue in her cervix instead of epithelial tissue.

From "The Immortal Life of Henrietta Lacks" by Rebecca Skloot