[nee-en-sef-uh-lon, -luh n]
noun, plural ne·en·ceph·a·lons, ne·en·ceph·a·la [nee-en-sef-uh-luh] /ˌni ɛnˈsɛf ə lə/.
  1. the more recent part of the brain in the evolutionary development of animals, including the cerebral cortex and its related structures.

Origin of neencephalon

First recorded in 1915–20; ne- + encephalon
Related formsne·en·ce·phal·ic [nee-en-suh-fal-ik] /ˌni ɛn səˈfæl ɪk/, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018