Lewis & Short

irrŭmo (inr-), āvi, ātum, 1, v. a. [ruma], to extend the breast to, to give suck; hence,

  1. I. In mal. part., Cat. 16, 1; Auct. Priap. 36, 5; Mart. 4, 50, 2.
  2. II. Transf.
    1. A. To treat in a foul or shameful manner, to abuse, deceive, Cat. 28, 9.
    2. B. Irrumata unda, i. e. defiled, Mart. 2, 70, 3.