- Menkes' syndrome - see Syndrome, Menkes'
- Menolipsis 626.0
- Menometrorrhagia 626.2
- Menopause, menopausal (symptoms) (syndrome) 627.2
- Menorrhagia (primary) 626.2
- Menorrhalgia 625.3
- Menoschesis 626.8
- Menostaxis 626.2
- Menses, retention 626.8
- Menstrual - see also Menstruation
- Menstruation
- Mentagra (see also Sycosis) 704.8
- Mental - see also condition
- Meralgia paresthetica 355.1
- Mercurial - see condition
- Mercurialism NEC 985.0
- Merergasia 300.9
- Merkel cell tumor - see Carcinoma, Merkel cell
- Merocele (see also Hernia, femoral) 553.00
- Meromelia 755.4
- Merosmia 781.1
- MERRF syndrome (myoclonus with epilepsy and with ragged red fibers) 277.87