third ventricle: a narrow ventricle in the midplane below the corpus callosum; communicates with the fourth ventricle via the Sylvian aqueduct
ventricle: one of four connected cavities in the brain; is continuous with the central canal of the spinal cord and contains cerebrospinal fluid
colorado river hemp: tall-growing annual of southwestern United States widely grown as green manure; yields a strong tough bast fiber formerly used by Indians for cordage