Lewis Short
(adjective) : incrēdundus (incrēdendus), a, um, 2. in-credo
* Not to be believed, incredible (Appuleian): fabula,App. M. 2, p. 120, 15: potentiae caerimoniarum,id. Flor. 2, p. 351: illecebrae frugum,id. Mag. p. 304, 25.
Charlton T. Lewis, Charles Short, A Latin Dictionary