| Acronym | Definition |
|---|
| MMSI➣Merit Medical Systems, Inc. (est. 1987; South Jordan, UT) |
| MMSI➣Maritime Mobile Service Identity |
| MMSI➣Miniature Munitions/Store Interface |
| MMSI➣Managing Microsoft School Infrastructures (book) |
| MMSI➣Military Miniature Society of Illinois |
| MMSI➣Military Membership Status Identifier |