| Rank | Abbreviation | Meaning |
|---|
| ***** | MCOS | Minimum Conditions of Satisfaction
| |
| **** | MCOS | Mercury Computer Operating System
| |
| ** | MCOS | Multi-Channel Objective System
| |
| * | MCOS | Material Cost of System
| |
| * | MCOS | Multicultural Council of Saskatchewan
| |
| * | MCOS | Managed Care Organization
| |
| * | MCOS | Major Combat Operations
| |
| * | MCOS | mixed coronary obstructive syndrome
| |
| * | MCOS | Microprogrammable Computer Operating System
| |
| * | MCOS | Model Course of Study
| |
| * | MCOS | Montpelier Chamber Orchestra Society
| |
| * | MCOS | Mission Critical Operating Systems
| |
| * | MCOS | Modern Church of Satan
| |
| * | MCOS | Messaging Class of Service
| |
| * | MCOS | MACROSE INDUSTRIES CORP.
| |
| * | MCOS | Mac Crystal Oscillator Speedup
| |
| * | MCOS | Mountaineering Council of Scotland
| |
| * | MCOS | Managed care organizations should
| |
| * | MCOS | Member of Canadian Oculoplastic Society
| |
| * | MCOS | Multi-Canister Overpacks
| |
| * | MCOS | Mission Critical Occupations
| |
| * | MCOS | Managed Care Organizations Serving
| |
| * | MCOS | Music Copyright Operational Services
| |
| * | MCOS | Milwaukee Clinic of Orthopedic Surgery
| |
| * | MCOS | Managed Care Organisations
| |