Lewis Short
(adjective) : in-frăgĭlis, e
* That cannot be broken to pieces.
* Lit.: adamas,Plin. H. N. 20 prooem. § 2.
* Trop., strong, that cannot be weakened: vox,Ov. Tr. 1, 5, 53: animi,Sen. Vit. B. 9.
Charlton T. Lewis, Charles Short, A Latin Dictionary