Dictionary.com

blood-brain barrier

[ bluhd-breyn ]
/ ˈblʌdˈbreɪn /
Save This Word!

noun Physiology.
a layer of tightly packed cells that make up the walls of brain capillaries and prevent substances in the blood from diffusing freely into the brain: passage across the cell membranes is determined by solubility in the lipid bilayer or recognition by a transport molecule.
QUIZ
QUIZ YOURSELF ON AFFECT VS. EFFECT!
In effect, this quiz will prove whether or not you have the skills to know the difference between “affect” and “effect.”
Question 1 of 7
The rainy weather could not ________ my elated spirits on my graduation day.
Meet Grammar CoachWrite or paste your essay, email, or story into Grammar Coach and get grammar helpImprove Your Writing
Meet Grammar CoachImprove Your Writing
Write or paste your essay, email, or story into Grammar Coach and get grammar help

Origin of blood-brain barrier

First recorded in 1940–45
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use blood-brain barrier in a sentence

Medical definitions for blood-brain barrier

blood-brain barrier

n.
A physiological mechanism that alters the permeability of brain capillaries so that some substances, such as certain drugs, are prevented from entering brain tissue, while other substances are allowed to enter freely.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for blood-brain barrier

blood-brain barrier

A physiological mechanism that alters the permeability of capillaries in the brain, so that some substances, such as certain drugs, are prevented from entering brain tissue, while other substances are allowed to enter freely.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for blood-brain barrier

blood-brain barrier

The separation of the brain, which is bathed in a clear cerebrospinal fluid, from the bloodstream. The cells near the capillary beds external to the brain selectively filter the molecules that are allowed to enter the brain, creating a more stable, nearly pathogen-free environment.

notes for blood-brain barrier

Oxygen, glucose, and white blood cells are molecules that are able to pass through this barrier. Red blood cells cannot.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
FEEDBACK