Lewis & Short

inquīsītor, ōris, m. [inquiro], a searcher.

  1. I. Lit., one who searches for a suspected person, an inquisitor, tracker, detective, spy: scrutatur vestigia (canis) atque persequitur, comitantem ad feram inquisitorem loro trahens, the hunter, Plin. 8, 40, 61, § 147: se ab inquisitoribus pecunia redimere, Suet. Caes. 1: inquisitores algae, they who search the very sea-weed, Juv. 4, 49.
  2. II. Transf., an examiner, investigator.
    1. A. In gen.: rerum inquisitorem decet esse sapientem, Cic. Fragm. Ac. ap. Aug. cont. Ac. 2, 11: rerum naturae, Sen. Q. N. 6, 13, 2.
    2. B. In partic., one who searches for proofs to support an accusation, Cic. Verr. 1, 2, 6: Norbanus legatus et inquisitor reum postulavit, Plin. Ep. 3, 9, 29; Sen. Ben. 5, 25, 2; Tac. A. 15, 66.