cerebrospinal fluid

Definition of cerebrospinal fluid
National Cancer Institute

cerebrospinal fluid

(seh-REE-broh-SPY-nul FLOO-id)
The fluid that flows in and around the hollow spaces of the brain and spinal cord, and between two of the meninges (the thin layers of tissue that cover and protect the brain and spinal cord). Cerebrospinal fluid is made by tissue called the choroid plexus in the ventricles (hollow spaces) in the brain. Also called CSF.

Source: NCI Dictionary of Cancer Terms