GMSO
| Acronym | Definition |
|---|---|
| GMSO | Global Markets Shared Operations (banking) |
| GMSO | Gruppo Molisano Studi Ornitologici (Italian: Molise Ornithological Studies Group; est. 1992) |
| GMSO | Greater Marlborough Symphony Orchestra (Marlborough, MA) |
| GMSO | Graduate Management Student Organization (Worcester Polytechnic Institute) |