Here is my bit of crazy... correcting lay people online when it isn't necessary nor appropriate. It isn't reasonable. Doesn't happen that often but sometimes I just can't help it. This is ego dystonic.
DSM-5 criteria for obsession
Obsessions are defined in the DSM-5 as follows:
Recurrent and persistent thoughts, urges, or images that are experienced, at some time during the disturbance as intrusive and inappropriate, and that cause marked anxiety and distress.
The person attempts to suppress or ignore such thoughts, impulses, or images or to neutralize them with some other thought or action.
DSM-5 criteria for compulsion
Compulsions are defined by (1) and (2) as follows:
Repetitive behaviors (eg, hand washing, ordering, checking) or mental acts (eg, praying, counting, repeating words silently) performed in response to an obsession or according to rules that must be applied rigidly. The behaviors are not a result of the direct physiologic effects of a substance or a general medical condition.
The behaviors or mental acts are aimed at preventing or reducing distress or preventing some dreaded event or situation. However, these behaviors or mental acts either are not connected in a way that could realistically neutralize or prevent whatever they are meant to address or they are clearly excessive.
It has to be ego dystonic. They (obsessions and compulsions) have to cause significant distress, or are excessively time consuming, or significantly interfere with social/academic/occupational/normal routines.
obsessive-compulsive personality disorder (OCPD) should not be confused with OCD. The diagnosis of OCPD refers to an individual who is preoccupied with orderliness, perfectionism, and mental and interpersonal control, at the expense of flexibility, openness, and efficiency; a pattern that typically emerges in early adulthood. They often display perfectionism, excessive devotion to work, rigidity, and/or miserliness (for further details, see DSM-5). This disorder can be ego syntonic.
Sources: knowledge, DSM-V, Medscape.