[pey-lee-en-sef-uh-lon; especially British pal-ee-]
noun, plural pa·le·en·ceph·a·la [pey-lee-en-sef-uh-luh; especially British pal-ee-] /ˌpeɪ li ɛnˈsɛf ə lə; especially British ˌpæl i-/.
(no longer in technical use) the more primitive part of the brain in the evolutionary development of animals, including all parts except the cerebral cortex and its related structures.
Origin of paleencephalon
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019