| Abbreviation | Definition |
|---|---|
| MSGB | Madison Square Garden Boxing, Inc. (fight promotion) |
| MSGI | Media Services Group Inc |
| MSGI | MurTech Services Group, Inc |
| MSGL | Media Services Group Ltd |
| MSHI | Man Sang Holdings Inc |
| MSI | Macintyre Strater Internatational |
| MSI | Management Services Incorporated |
| MSI | Mayfair Storage Interconnect |
| MSI | Meeting Services Inc |
| MSI | Metapath Software International |
| MSI | Micro Star International |
| MSI | Micro Systems International |
| MSI | Molecular Simulations, Inc. |
| MSI | Molecular Simulations, Incorporated |
| MSI | Montgomery Soccer Inc |
| MSI | Motorola Solutions Inc |
| MSI | Much Salt Incoming |
| MSI | Multispectral Solutions, Inc. |
| MSIC | Medical Savings Insurance Company |
| MSIF | Morgan Stanley Institutional Fund, Inc. |