per·verse / pərˈvərs/ • adj. (of a person or their actions) showing a deliberate and obstinate desire to behave in a way that is unreasonable or unacceptable, often in spite of the consequences: Kate's perverse decision not to cooperate. ∎ contrary to the accepted or expected standard or practice: in two general elections the outcome was quite perverse. ∎ Law (of a verdict) against the weight of evidence or the direction of the judge on a point of law. ∎ sexually perverted.DERIVATIVES: per·verse·ly adv. perversely, she felt nearer to tears now than at any other moment in the conversation.per·verse·ness n.per·ver·si·ty / -ˈvərsitē/ n. (pl. -ties) .