| MHRA | Medicines and Healthcare products Regulatory Agency |
| MI | Myokardinfarkt |
| MI | Mitralinsuffizienz |
| MI | Mitoseindex |
| MIBG | Meta-Iodbenzylguanidin |
| MIC | minimal inhibitory concentration |
| MIC | minimal invasive Chirurgie |
| MIDCAP | minimally invasive direct coronary artery pass |
| MIF | Migrationsinhibitionsfactor |
| MIH | melanotropin release inhibiting hormone |
| MIH | Molar-incisor hypomineralisation |
| MIK | maximale Immissionskonzentration |
| min | minimal |
| Min/ min | Minute |
| MIRL | macrophage Ia recruiting factor |
| MIS | Melanoma in situ |
| MKE | Kardio: Mitralklappenersatz |
| MKS | Maul- und Klauenseuche |
| ml | Milliliter |
| MLC | mixed lymphocyte culture |
| MLK | minimale Letalkonzentration |
| MLS | microphthalmia with linear skin defects |
| Mm | Musculi |
| MM | Muttermund |
| MM | Muttermilch |
| MM | Malignes Melanom |
| MMEF | maximaler mittexspiratorischer Atemstrom |
| MMG | Magnetomyogramm |
| mm Hg | Blutdruck Druckeinheit |
| MML | myelomonozytäre Leukämie |