/ Dictionary / Index N neoencephalon: Meaning and Definition of Find definitions for: ne•o•en•ceph•a•lon Pronunciation: (nē"ō-en-sef'u-lon", -lun), [key] — pl. -lons, -la neencephalon. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: neoencephalon (Thesaurus) neodymium neo-expressionism Related Content Daily Word Quiz: impetuous Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language