insopibilis

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

in-sōpībĭlis, e, adj. [2. in-sopio],

that cannot be lulled to sleep (post-class.): flamma, i. e. inextinguishable , Mart. Cap. 1, § 7: ignis, id. 9, § 910.