Lewis Short
(adjective) : fissĭlis, e, findo.
* That may be cleft or split, fissile (rare; not in Cic. or Caes.): robur,Verg. A. 6, 181; lignum,id. G. 1, 144; Plin. 16, 39, 73, § 187: arundo,id. 16, 36, 64, § 157: vena lapidis,id. 36, 17, 27, § 131.
* Cleft, split: stipes,Col. 9, 1, 3. —Comically transf.: ad focum si adesses, Non fissile haberes caput,you would not have had your crown cracked,Plaut. Aul. 3, 2, 26.
Charlton T. Lewis, Charles Short, A Latin Dictionary