Lesser Mortals may not under the word so here goes:
Anorgasmia (often related to delayed ejaculation in males) is a form of sexual dysfunction sometimes classified as a psychiatric disorder in which the patient cannot achieve orgasm, even with "adequate" stimulation. However, it can also be caused by medical problems such as diabetic neuropathy, multiple sclerosis, pelvic trauma, hormonal imbalances, total hysterectomy, spinal cord injury and cardiovascular disease. Anorgasmia is far more common in females than in males and is especially rare in younger men.
A common cause of anorgasmia, in both men and women, is the use of anti-depressants, particularly selective serotonin reuptake inhibitors (SSRIs). Though reporting of anorgasmia as a side-effect of SSRIs is not precise, it is estimated that 15-50% of users of such medications are affected by this condition[citation needed]. The chemical amantadine has been shown to relieve SSRI-induced anorgasmia in some, but not all, people.