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

Nakayama and his colleagues think these large proteins are employed on the cell membrane and somehow support interactions between the archaeon and its host. —Jake Buehler, Quanta Magazine, 24 Nov. 2025

Once frost appears, true dormancy that affects cell membranes and energy storage protects the plant until favorable environmental conditions return to break the plant out of dormancy. —Mary Marlowe Leverette, Southern Living, 14 Nov. 2025

The fossil chemicals in question are a special types of steranes, which are the geologically stable form of sterols, like cholesterol, that are found in the cell membranes of complex organisms. —Maria Azzurra Volpe, MSNBC Newsweek, 1 Oct. 2025

Immune System Support Omega-6 fatty acids influence immune function involved in inflammatory responses, strengthening immune cell membranes. —Amy Brownstein, Verywell Health, 1 Oct. 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