| Minnesota Association of Student Councils | Academic & Science |
| Maryland Association of Student Councils | Academic & Science |
| Marine Aquarium Society Of Colorado | Academic & Science |
| Micro Architecture Santa Cruz | Academic & Science |
| Micro Architecture at Santa Cruz | Academic & Science |
| Missouri Association of Student Councils | Academic & Science |
| Math and Science Challenge | Academic & Science |
| Member of Associated Stress Consultants (UK) | Academic & Science |
| Mountain Administrative Support Center | Academic & Science |
| Manitoba Agricultural Services Corporation | Business |
| Monroe Actors Stage Company | Business |
| Management Account Structure Codes | Business Management |
| Michigan Association of Student Councils | Community |
| Massachusetts Association of School Committees | Community |
| Midwest Alliance Soccer Conference | Community |
| Multicultural Arts for Schools and Communities | Community |
| Massachusetts Association of Student Councils | Community |
| Multinational Arabidopsis Steering Committee | Community |
| Mas Controller | Computing |
| Microsoft Access Script Command | Computing |
| Marketing Association of Seneca College | Educational Institute |
| Myomer Accelerator Signal Circuitry | Electronics |
| Multi Angle Snowflake Camera | General |
| Manually Annotated Sub Corpus | General |
| Movies Anime Shows Comics | General |
| Monitoring and Security of Containers | General |
| Multiple Active Site Correction | General |
| Marine Aquarium | General |
| Mammary Analogue Secretory Carcinoma | General |
| Mitsubishi Active Stability Control | General |
| Midget And Sprite Club | General |
| Multi Agent Satisficing Control | General |
| Manuscripts Archives And Special Collections | General |
| Multicast Address Set Claim | General |
| Modular Advanced Signal Channelizer | General |
| Municipal Association of South Carolina | Governmental |
| Manipulated Autologous Structural Cell | Governmental |
| masculine | Medical |
| Medical Academic Staff Committee | Medical |
| Medical Advisers Support Centre | Medical |
| Male Abuse Survivors Centre | Medical |
| Minimal Access Surgery Center | Medical |
| Military Audiology Short Course | Military and Defence |
| Mid-American Soccer Classic | Sports |
