obsessive–compulsive disorder/ əbˌsɛs.ɪv kəmˈpʌl.sɪv dɪˌsɔrdər / noun
a psychological condition where a person has certain thoughts repeatedly or feels the need to perform certain actions repeatedly:
Obsessive–compulsive disorder affects about one person in forty at some point in their life.
The abbreviation is OCD:
OCD can be a very debilitating condition. | OCD sufferers often feel the need to check things repeatedly.