prŏbātōrĭa

ae, f.
I. a letter of recommendation (from the emperor), a certificate of qualification (postclass.): sacra probatoria, Cod. Just. 12, 58, 2: emissa sacri scrinii probatoria, ib. 12, 60, 6; 12, 36, 7.
Lewis & Short
A Latin Dictionary, 1879
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