| GMSC | Gateway Mobile Services Switching Center 
| Others |
| GMSC | Gateway Mobile Switching Centre
| Others |
| GMSC | Geelong Motor Sport Club
| Others |
| GMSC | General Manager Search Committee
| Others |
| GMSC | General Medical Services Committee
| Others |
| GMSC | Genetic Manipulation Supervisory Committee
| Others |
| GMSC | Genetic Modification Safety Committee
| Others |
| GMSC | Gingival Mesenchymal Stem Cells
| Others |
| GMSC | Give Me Some Cheese
| Others |
| GMSC | Global Mobile Satellite Communication
| Others |
| GMSC | Global Mobile Satellite Communications
| Others |
| GMSC | Goizueta Marketing Strategy Consultancy
| Others |
| GMSC | Gold Medal Swim Club
| Others |
| GMSC | Good Morning South Columbia
| Others |
| GMSC | Goodyear Motor Sports Club
| Others |
| GMSC | Grande Maumelle Sailing Club
| Others |
| GMSC | Greater Miami Service Corps
| Others |
| GMSC | Greater Miami Ski Club
| Others |
| GMSC | Greater Moncton Sewage Commission
| Others |
| GMSC | Greater Moncton Sewerage Commission
| Others |
| GMSC | Green Mountain Saab Club
| Others |
| GMSC | Greenwood Memorial Swim Club
| Others |
| GMSC | Gulf Masters Swim Committee
| Others |