[TA] (1) the frontal or anterior division of the lateral ventricle of the brain, extending forward from the Monro interventricular foramen;lateral ventricle (2) the anterior horn or anterior (ventral) gray column of the spinal cord as appearing in cross section. The anterior horn is composed of the spinal laminae VIII and IX [TA] of Rexed with portions of VII also extending into its geographical boundaries in lumbosacral and cervical levels. The nuclei of the anterior horn are the anterolateral nucleus [TA] or ventrolateral nucleus [TAalt] (nucleus anterolateralis [TA]), anterior nucleus [TA] (nucleus anterior [TA]), anteromedial nucleus [TA] or ventromedial nucleus [TAalt] (nucleus anteromedialis [TA]), posterolateral nucleus [TA] or dorsolateral nucleus [TAalt] (nucleus posterolateralis [TA]), retroposterior lateral nucleus [TA] or retrodorsal lateral nucleus [TAalt] (nucleus retroposterolateralis [TA]), posteromedial nucleus [TA] or dorsomedial nucleus [TAalt] (nucleus posteromedialis [TA]), central nucleus [TA] (nucleus centralis [TA]), and the accessory nucleus and phrenic nucleus (both found in cervical levels only).anterior column, gray columns, under column. SYN: cornu anterius [TA], ventral horn.