| Acronym | Definition |
|---|
| CIIS➣California Institute of Integral Studies |
| CIIS➣China Institute of International Studies (Beijing, China) |
| CIIS➣Comitato Interministeriale per le Informazioni e la Sicurezza (Italian: Interministerial Committee for Information and Security) |
| CIIS➣Center for Integrated Intelligence Systems |
| CIIS➣Controlled Items Inventory System |
| CIIS➣Client Integration Implementation Service |
| CIIS➣Compatibility, Interoperability, Integration and C4 Supportability |