- Diaphoresis (excessive) NEC (see also Hyperhidrosis) 780.8
 - Diaphragm - see condition
 - 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