Lewis Short
(adjective) : ostentārĭus, a, um, ostentum
* Of or relating to prophetic indications, prophetic (post-class.): ostentaria novitas (al. ostentatoria),Mart. Cap. 2, § 151.
* Subst.: ostentārĭum, ii, n., a book of prognostics: Tuscum,Macr. S. 3, 7: arborarium,id. ib. 2, 16.
Charlton T. Lewis, Charles Short, A Latin Dictionary