- Mibelli's disease 757.39
- Mice, joint (see also Loose, body, joint) 718.1
- Micheli-Rietti syndrome (thalassemia minor) 282.46
- Michotte's syndrome 721.5
- Micrencephalon, micrencephaly 742.1
- Microalbuminuria 791.0
- Microaneurysm, retina 362.14
- Microangiopathy 443.9
- Microcalcification, mammographic 793.81
- Microcephalus, microcephalic, microcephaly 742.1
- Microcheilia 744.82
- Microcolon (congenital) 751.5
- Microcornea (congenital) 743.41
- Microcytic - see condition
- Microdeletions NEC 758.33
- Microdontia 520.2
- Microdrepanocytosis (thalassemia-Hb-S disease) 282.41
- Microembolism
- Microencephalon 742.1
- Microfilaria streptocerca infestation 125.3
- Microgastria (congenital) 750.7
- Microgenia 524.06