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

See Examples For:

epithelial

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

"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 adult stem cells were limited in function and could only mature into retinal pigment epithelial cells.

From Science Daily ● Nov. 22, 2025

This limitation is crucial, he added, because the interior of each cyst -- essentially a sealed chamber lined with epithelial cells -- is the location where disease-driving activity occurs.

From Science Daily ● Nov. 19, 2025

The epithelial cells have the ability to constrict to change the absorption of light, controlling the subject’s color and texture on a cell-by-bell basis.

From "Boy 2.0" by Tracey Baptiste