epencephalic,a.Anat.|ɛˌpɛnsɪˈfælɪk| [f. epencephal-on + -ic.] Of or pertaining to the epencephalon; covering the epencephalon. 1851[see rhinencephalon].1854Owen in Circ.Sc. (c 1865) II. 53/2 Epencephalic arch.1880Günther Fishes 85 Epencephalic arch, composed of the occipitals.