pain: An unpleasant sensation that can variety from mild, localized pain to discomfort. pain has each physical and emotional components. The physical part of pain consequences from nerve stimulation. pain may be contained to a discrete region, as in an damage, or it could be greater diffuse, as in issues like fibromyalgia. pain is mediated with the aid of specific nerve fibers that convey the ache impulses to the mind wherein their aware appreciation can be modified with the aid of many elements.