- Didelphys, didelphic (see also Double uterus) 752.2
- Didymitis (see also Epididymitis) 604.90
- Died - see also Death
- Dientamoeba diarrhea 007.8
- Dietary
- Dietl's crisis 593.4
- Dieulafoy lesion (hemorrhagic)
- Difficult
- Difficulty
- Diffuse - see condition
- Diffused ganglion 727.42
- Digestive - see condition
- Dihydropyrimidine dehydrogenase disease (DPD) 277.6
- Diktyoma (M9051/3) - see Neoplasm, by site, malignant
- Dilaceration, tooth 520.4
- Dilatation
- Dilated, dilation - see Dilatation
- Diminished
- Diminuta taenia 123.6
- Diminution, sense or sensation (cold) (heat) (tactile) (vibratory) (see also Disturbance, sensation) 782.0
- Dimitri-Sturge-Weber disease (encephalocutaneous angiomatosis) 759.6
- Dimple