A psychological disorder characterized by the compulsive need to check things, have particular thoughts, or to perform certain routines repeatedly
Obsessive-compulsive disorder is a psychological disorder in which the individual has persistent and repetitive intrusion of unwanted thoughts, urges, or actions that the individual is unable to prevent. The compulsive thoughts may consist of single words, ideas, or ruminations often perceived by the sufferer as nonsensical. The repetitive urges or actions vary from simple movements to complex rituals. The anxiety or distress is the underlying emotion or drive state, and the ritualistic behaviour is a learned method of reducing the anxiety. People with Obsessive-compulsive disorder are unable to control these compulsive thoughts and activities. Examples of situations showing obsessive-compulsive disorder is repetitive hand washing, repeatedly checking to see if the door is locked, and counting of things over and over.
There are no definite causes of obsessive-compulsive disorder but researchers look for ways in which stress and environmental factors may play a role.1 There may be genetic factor at play as well. A mutation in the human serotonin transporter gene, hSERT, in unrelated families with OCD was reported.2
It should not be confused with another psychological disorder, obsessive-compulsive personality disorder.
Abbreviation / Acronym: OCD
- compulsive neurosis
- obsessive-compulsive neurosis
1 Obsessive-Compulsive Disorder, OCD. NIMH. Retrieved from 
2 Ozaki N, Goldman D, Kaye WH, Plotnicov K, Greenberg BD, Lappalainen J, Rudnick G, Murphy DL (2003). "Serotonin transporter missense mutation associated with a complex neuropsychiatric phenotype".Mol. Psychiatry 8 (11): 933–6.