ostiolum

A New Latin Dictionary by Charlton T. Lewis Ph.D. and Charles Short, LL. D.

ostĭŏlum, i, n. dim. [ostium],

a little door (post-Aug.), Col. 8, 14, 1: ostiola olitoria, Plin. 19, 8, 38, § 125: abscondita, Vulg. Dan. 14, 20.