- Diplopia: double vision. See treatment guide: 1.
- Disorientation: (disoriented). Unable to correctly judge person, place, time, and event; incorrect answer to A&Ox3 or A&Ox4 questions.
- Dysdiadochokinesia: impaired ability to perform rapid alternating movements. Adiadochokinesia is the complete inability to perform rapid alternating movements.
- Dysmetria: lack of coordination of movement with undershooting or overshooting of the intended target. A type of ataxia. Seen in cerebellar disorders.
- Dyspnea: difficulty breathing. (WNL = 12-20 breaths/min)
- Dystrophic: tissue of the body wastes away, e.g. Muscular Dystrophy
- Reduction: a surgical procedure to restore a fracture or dislocation to the correct alignment.
- Stump: (considered politically incorrect) residual limb from amputation (elective & non-elective).