blood-brain barrier

noun

: a naturally occurring barrier created by the modification of brain capillaries (as by reduction in fenestration and formation of tight cell-to-cell contacts) that prevents many substances from leaving the blood and crossing the capillary walls into the brain tissues

Examples of blood-brain barrier in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
This occurs when cancer cells migrate through the blood-brain barrier. Vanessa Etienne, People.com, 13 Feb. 2025 Berberine crosses the blood-brain barrier, influencing its potential for brain health. Amy Brownstein, Ms, Rdn, Verywell Health, 7 Feb. 2025 For instance, the tiniest pieces can cross the blood-brain barrier. Paul Smaglik, Discover Magazine, 4 Feb. 2025 Children could be at highest risk from plastic in the brain Because the brain is relatively protected by the blood-brain barrier, there is at least some defense by the body. Elizabeth Weise, USA TODAY, 3 Feb. 2025 See all Example Sentences for blood-brain barrier 

Word History

First Known Use

1934, in the meaning defined above

Time Traveler
The first known use of blood-brain barrier was in 1934

Dictionary Entries Near blood-brain barrier

Cite this Entry

“Blood-brain barrier.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/blood-brain%20barrier. Accessed 22 Feb. 2025.

Medical Definition

blood-brain barrier

noun
: a naturally occurring barrier created by the modification of brain capillaries (as by reduction in fenestration and formation of tight cell-to-cell contacts) that prevents many substances from leaving the blood and crossing the capillary walls into the brain tissues
abbreviation BBB

More from Merriam-Webster on blood-brain barrier

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