脉络丛

[ noun ]
a vascular plexus of the cerebral ventricles that regulate intraventricular pressure
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Choroid \Cho"roid\, a. [gr. ?; ? chorion + e'i^dos form.]
(Anat.)
resembling the chorion; as, the choroid plexuses of the
ventricles of the brain, and the choroid coat of the eyeball.
-- n. The choroid coat of the eye. See {Eye}.

{Choroid plexus} (Anat.), one of the delicate fringelike
processes, consisting almost entirely of blood vessels,
which project into the ventricles of the brain.