Lewis & Short

tractātor, ōris, m. [tracto].

  1. I. A slave among the Romans, who manipulated and suppled his master’s limbs while anointing them; a shampooer, Sen. Ep. 66, 53.
  2. II. A handler, treater of any thing. esp. of literary matters (post-class.): Origenes scaevus cavendusque tractator, Sid. Ep. 2, 9; 4, 11; Hier. in Helv. 6; Spart. Get. 4; Sulp. Sev. 1, 6.