| Abbreviations | Meaning |
 | MCM6 | Manual Of Clinical Microbiology, 6th Edition |
 | MCMI-III | Millon Clinical Multiaxial Inventory-III |
 | MCMLA | Midcontinental Chapter Of The Medical Library Association |
 | MCN | MCN: The American Journal Of Maternal/Child Nursing |
 | MCN | Molecular And Cellular Neuroscience |
 | MCNP | Massachusetts Coalition Of Nurse Practitioners |
 | MCO | Managed Care Organization |
 | MCO | Médecine Chirurgie Obstétrique |
 | MCP | Molecular & Cellular Proteomics[periodical] |
 | MCR | Molecular Cancer Research [periodical] |
 | MCRR | Medical Care Research And Review [periodical] |
 | MCRUD | Michigan Coalition To Reduce Underage Drinking |
 | MCS | Michigan Chiropractic Society |
 | MCS | Multiple Chemical Sensitivity |
 | MCSFA | Michigan Citizens For SmokeFree Air |
 | MCT | Molecular Cancer Therapeutics [periodical] |
 | MCTRF | Manitoba Cancer Treatment And Research Foundation |
 | MCU-PH | Maître De Conférences Des Universités-Praticien Hospitalier |
 | MD | Medicinae Doctor. Doctor Of Medicine |
 | MDA | Malaysian Dental Association |
 | MDA | Manitoba Dental Association |
 | MDA | Medical Directory Of Australia |
 | MDA | Michigan Deaf Association |
 | MDA | Michigan Dental Association |
 | MDA | Missouri Dental Association |
 | MDA | Montana Dental Association |
 | MDA | Muscular Dystrophy Association Australia |
 | MDA | Muscular Dystrophy Association USA |
 | MDAA | Minnesota Dental Assistants Association |
 | MDAC / ACDM | Muscular Dystrophy Association Of Canada / Association Canadienne De La Dystrophie Musculaire |
 | MDAV | Medical Defence Association Of Victoria |
 | MDCB | Medical Dosimetrists Certification Board |
 | MDCH | Michigan Department Of Community Health |
 | MDDS | Metro Denver Dental Society |
 | MDDS | Metropolitan District Dental Society |
 | MDF | Macular Degeneration Foundation |
 | MDFF | Muscular Dystrophy Family Foundation |
 | MDH | Minnesota Department Of Health |
 | MDHA | Maine Dental Hygienists Association |
 | MDHA | Manitoba Dental Hygienists Association |
 | MDHA | Michigan Dental Hygienists Association |
 | MDHA | Minnesota Dental Hygienists Association |
 | MDHA | Missouri Dental Hygienists Association |
 | MDHA | Montana Dental Hygienists Association |
 | MDM | Medical Decision Making [periodical] |
 | MDM | Médecins Du Monde. Doctors Of The World. |
 | MDO | Maladies à Déclaration Obligatoires. Notifiable Diseases. |
 | MDPA | Malaysian Private Dental Practitioners Association |
 | MDPH | Massachusetts Department Of Public Health |
 | MDPI | Molecular Diversity Preservation International |