- Mammoplasia 611.1
- Management
- Mangled NEC (see also nature and site of injury) 959.9
- Mania (monopolar) (see also Psychosis, affective) 296.0
- Manic-depressive insanity, psychosis, reaction, or syndrome (see also Psychosis, affective) 296.80
- Manifestations, rheumatoid
- Mankowsky's syndrome (familial dysplastic osteopathy) 731.2
- Mannoheptulosuria 271.8
- Mannosidosis 271.8
- Manson's
- Mansonellosis 125.5
- Manual - see condition
- Maple bark disease 495.6
- Maple bark-strippers' lung 495.6
- Maple syrup (urine) disease or syndrome 270.3
- Marable's syndrome (celiac artery compression) 447.4
- Marasmus 261
- Marble
- Marburg disease (virus) 078.89
- March
- Marchand multiple nodular hyperplasia (liver) 571.5
- Marchesani (-Weill) syndrome (brachymorphism and ectopia lentis) 759.89
