Lewis & Short

persĕcūtor, ōris, m. [perscrutator].

      1. 1. A pursuer (post-class.): flagitiorum turpium, Capitol. Alb. 11, 7.
      2. 2. A persecutor of Christians, Mort. Persec. 1; id. Inst. 5, 23, 1: Ecclesiae, Hieron. Ep. ad Helv. 3: sub ense persecutoris pati, Prud. στεφ. 1, 28; Vulg. 1 Tim. 1, 13.
      3. 3. A prosecutor, plaintiff, Dig. 48, 3, 7.