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.
The powerful blood-brain barrier, the thinking goes, keeps the organ mostly free from outside invaders. Yasemin Saplakoglu, WIRED, 5 Jan. 2025 This study suggests that small-particle HDL might help maintain this gray matter by crossing the blood-brain barrier to support brain function and protect against atrophy. Hannah Singleton, Health, 15 Jan. 2025 It can be distributed throughout the body, crossing the blood-brain barrier and the placenta easily and potentially causing severe birth defects. Sallie Tisdale, Harper's Magazine, 2 Dec. 2024 This could allow therapies that were previously ineffective — due to their inability to cross the blood-brain barrier to reach their target in the central nervous system — to directly target tissues. Melissa Rudy, Fox News, 31 Dec. 2024 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 10 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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