Lewis Short
(adjective) : testĭmōnĭālis, e, testimonium
* Of, belonging to, or serving for evidence, testimonial (late Lat.).
* Adj.: comparatio,Tert. adv. Psych. 16 fin.
* Subst.: te-stĭmōnĭāles, ĭum, f. (sc. litterae), testimonials, Cod. Th. 7, 20, 12; 7, 21, 4; Veg. Mil. 3, 2.
Charlton T. Lewis, Charles Short, A Latin Dictionary