cell membrane

noun

plural cell membranes

: a membrane of a cell

especially : a semipermeable limiting layer of cell protoplasm consisting of a fluid phospholipid bilayer with intercalated proteins : plasma membrane

Despite being much maligned in the popular press, cholesterol plays a crucial role in organizing cell membranes and controlling their physical properties.

—Amanda Yarnell

… a cascade of reactions culminating in the transfer of a phosphate group to a protein complex that carries ions across the cell membrane.

—Science News

Examples of cell membrane in a Sentence

Recent Examples on the Web

When exposed to ultrasound at the target site, these bubbles temporarily create tiny pores in the BBB’s cell membrane, allowing drugs to pass through. —Jenny Lehmann, Discover Magazine, 26 Feb. 2025

Olive oil and cell membranes are composed of the same oily molecules, called fatty acids. —Douglas Fox, Scientific American, 1 Apr. 2018

Life on an acidic world might use a different set of lipids than the ones in our cell membranes, but the physics of membrane formation would look the same, if Petkowski and his colleagues are right. —Kiona N. Smith, Space.com, 20 Feb. 2025

First observed in a common lab bacterium only 14 years ago, bacterial nanotubes are structures made of cell membrane that allow nutrients and resources to flow between two or more cells. —Veronique Greenwood, WIRED, 9 Feb. 2025

Word History

First Known Use

1840, in the meaning defined above

Rhymes for cell membrane

• aeroplane
• appertain
• ascertain
• capitaine
• cassegrain
• cellophane
• chatelaine
• counterpane
• entertain
• gethsemane
• halothane
• hurricane

Kids Definition

cell membrane

noun

: a semipermeable outside layer surrounding the contents of a cell

Medical Definition

cell membrane

noun

: a membrane of a cell

especially : plasma membrane