cell membrane


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 Consume Healthy Fats Fats, particularly those rich in omega-3 fatty acids, support the structure and function of cell membranes, including those of hormone-producing cells. Nick Blackmer, Verywell Health, 11 Mar. 2024 The company says the good bacteria found in the products strengthen cell membranes, making skin more elastic, resilient and immune to inflammation. Miami Herald, 30 Jan. 2024 Serotonin can’t get through the cell membrane, which is why people don’t hallucinate when taking antidepressants like Prozac or Zoloft. Jon Brodkin, Ars Technica, 2 Oct. 2023 Furthermore, estrogen appears to have a stabilizing effect on cell membranes that might otherwise rupture from acute stress brought on by heat and exercise. Cara Ocobock, Scientific American, 19 Oct. 2023 Boosting efficacy, researchers add an agent that turns cell membranes into fluid, allowing the drug to penetrate more deeply into tissues. Scott Lafee, San Diego Union-Tribune, 28 Nov. 2023 Estrogen also stabilizes cell membranes that might otherwise be damaged or rupture due to the stress of exercise. Sarah Lacy, Discover Magazine, 27 Nov. 2023 Eukaryotes create vast quantities of fat molecules known as sterols, a type of steroid that’s a critical component of cell membranes. Yasemin Saplakoglu, Quanta Magazine, 23 Oct. 2023 Once your body reaches a hundred and five or a hundred and six degrees, your limbs might convulse, and, at a hundred and seven, your cell membranes melt, and proteins inside the cells unfold. Carolyn Kormann, The New Yorker, 6 Sep. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'cell membrane.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1840, in the meaning defined above

Time Traveler
The first known use of cell membrane was in 1840

Dictionary Entries Near cell membrane

Cite this Entry

“Cell membrane.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cell%20membrane. Accessed 17 Apr. 2024.

Kids Definition

cell membrane

: a semipermeable outside layer surrounding the contents of a cell

Medical Definition

cell membrane

: a membrane of a cell
especially : plasma membrane
Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!