| CIAO | Goodbye(in Italian) | 再见 |
| CIAO | Component-Integrated ACE ORB | 组件集成ACE ORB |
| CIAO | Commodity Import Analysis & Operation (USDA) | 商品进口分析及运行(USDA) |
| CIAO | Carleton in and Out (Carleton College queer centered group) | 卡莱顿进进出出（卡莱顿学院以同性恋为中心的群体） |
| CIAO | Centre for Informatics and Applied Optimization (University of Ballarat, Australia) | 信息学和应用优化中心（澳大利亚巴拉特大学） |
| CIAO | Critical Infrastructure Assurance Office | 关键基础设施保证办公室 |
| CIAO | Component Integrated Ace Orb | 组件集成Ace Orb |
| CIAO | CLAM-INKA-OMRS | 蛤蜊 |
| CIAO | Coronagraphic Imager with Adaptive Optics (National Astronomical Observatory of Japan) | 自适应光学日冕成像仪（日本国家天文台） |
| CIAO | Chandra Interactive Analysis of Observations | 钱德拉观测交互分析 |
| CIAO | Columbia International Affairs Online | 哥伦比亚国际事务在线 |
| CIAO | Council on International and Area Outreach (University of Tennessee) | 国际和地区外联委员会（田纳西大学） |
| CIAO | Check It All Out | 查看全部内容 |
| CIAO | Commitment Independence Attendance And Ownership | 承诺独立出席和所有权 |
| CIAO | Clinical Information Access Online | 在线临床信息访问 |
| CIAO | CiAO Is Aspect-Oriented | CiAO面向方面 |
| CIAO | Centro Informazioni Accoglienza Orientamento (Italy) | 东方信息中心（意大利） |
| CIAO | Cultural Italian American Organization | 意大利-美国文化组织 |