investigatrix

Learned borrowing from Latin investīgātrīx.^[1] By surface analysis, investigator +‎ -trix.

investigatrix (plural investigatrices)

1. Female equivalent of investigator.

   Synonym: investigatress

   • 1843, “Passages at the German Brunnen”, in The Metropolitan Magazine, volume XXXVII, Saunders and Otley, page 357:

     Our indefatigable investigatrix quickly brought us more positive information. She had actually overheard Sir John lay his heart and fortune at Miss Beechwood’s feet, without mentioning his hand.

From investīgō, investīgātum (“to track or trace out”, verb) +‎ -trīx f (“-ess”, agentive suffix).

• (Classical Latin) IPA^(key): [ɪn.wɛs.tiːˈɡaː.triːks]
• (modern Italianate Ecclesiastical) IPA^(key): [iɱ.ves.t̪iˈɡaː.t̪riks]

investīgātrīx f (genitive investīgātrīcis); third declension

1. female equivalent of investigator
   • c. 410–420, Martianus Capella, De Nuptiis Philologiae et Mercurii, book V, § 442:

     Inventio est quaestionum argumentorumque sagax investigatrixque comprehensio.

     (please add an English translation of this quotation)

   • a. 1259, Matthew Paris, Chronica Majora:

     Hoc autem rationi constat esse dissonum et omni iustitiae, immo contra logicae regulam, quae est investigatrix veritatis infallibilis.

     (please add an English translation of this quotation)

Third-declension noun.

• → English: investigatrix