- Diaphragmalgia 786.52
- Diaphragmitis 519.4
- Diaphyseal aclasis 756.4
- Diaphysitis 733.99
- Diarrhea, diarrheal (acute) (autumn) (bilious) (bloody) (catarrhal) (choleraic) (chronic) (gravis) (green) (infantile) (lienteric) (noninfectious) (presumed noninfectious) (putrefactive) (secondary) (sporadic) (summer) (symptomatic) (thermic) 787.91
- Diastasis
- Diastema, teeth, tooth 524.30
- Diastematomyelia 742.51
- Diataxia, cerebral, infantile 343.0
- Diathesis
- Diaz's disease or osteochondrosis 732.5
- Dibothriocephaliasis 123.4
- Dibothriocephalus (infection) (infestation) (latus) 123.4
- Dicephalus 759.4
- Dichotomy, teeth 520.2
- Dichromat, dichromata (congenital) 368.59
- Dichromatopsia (congenital) 368.59
- Dichuchwa 104.0
- Dicroceliasis 121.8
- Didelphys, didelphic (see also Double uterus) 752.2
- Didymitis (see also Epididymitis) 604.90
- Died - see also Death