| OPERA | On-Line Periodicals and Research Area (IEEE) | 在线期刊和研究领域（IEEE） |
| OPERA | Operational Programme for the Exchange of Weather Radar Information (EUMETNET) | 气象雷达信息交换业务方案（EUMETNET） |
| OPERA | Open PLC European Research Alliance | 开放式PLC欧洲研究联盟 |
| OPERA | Organised Programme of Experimentation and Research into ATM | 有组织的ATM实验和研究计划 |
| OPERA | Offers and Prospectuses Electronic Repository and Access (Singapore) | 提供和展望电子存储库和访问（新加坡） |
| OPERA | Office of Program Evaluation & Risk Analysis | 办公室的项目评估、风险分析 |
| OPERA | Out-Performance Equity Redeemable in Any Asset (convertible bond) | 可在任何资产中赎回的业绩外股权（可转换债券） |
| OPERA | Officer Professional Effectiveness Review for the Army (Australian Army) | 陆军军官职业效能评估（澳大利亚陆军） |
| OPERA | Open Process Engine For Reliable Activities | 用于可靠活动的开放流程引擎 |