An unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage.

This technical description of pain recognizes both the physiologic and affective nature of the pain experience. Pain is a highly personal, subjective experience that can only be accurately described by the individual who is experiencing pain.
Recognition and acceptance of the subjectivity of pain are among the most challenging aspects of patient care; health care providers must intervene and treat patients on the basis of self-reporting of the pain experience. In recent years, definitions of pain have been further refined to include the fact that a person's inability to verbally communicate does not preclude the possibility that pain is present, nor does it negate the responsibility of health care providers to treat it.

Adapted from IASP Taxonomy. Internet. Accessed on February 10, 2016.