Obsessive-compulsive disorder

A disorder characterized by recurrent intrusive thoughts (obsessions) that prompt the performance of neutralizing rituals (compulsions). Typical obsessions involve themes of contamination, dirt, or illness (fearing that one will contract or transmit a disease) and doubts about the performance of certain actions (e.g., an excessive preoccupation that one has neglected to turn off a home appliance).

Common compulsive behaviors include repetitive cleaning or washing, checking, ordering, repeating, and hoarding. The obsessions and compulsions are time consuming, cause significant distress, and interfere with functioning.

Adapted from the APA Dictionary of Psychology