| Acronym | Definition |
|---|
| RII | Risk Informed Inspection |
| RII | Routing Information Identifier |
| RII | Revue de l'Ingénieur Industriel (French: Journal of Industrial Engineering; Belgium) |
| RII | Routing Information Indicator |
| RII | Remote Ignition Interrupter (monster truck emergency power switch) |
| RII | Relevant Information and Intelligence |
| RII | Required Inspection Item (FAA) |
| RII | Request for Intelligence Information |
| RII | Registro de Industrias Integradas (Spanish: Registration Integrated Industries) |
| RII | Reform of International Institutions |
| RII | Reinvestment & Infrastructure Initiative |
| RII | Required Item Inspection (aviation; FAA) |
| RII | Required Item Installation |
| RII | Réseau International des Ingénieurs (French: International Network of Engineers) |
| RII | Robinsons Inn, Inc. |
| RII | Reactive Infiltration Instability (geology) |
| RII | Réseau International Immobilier (French: International Real Estate Network) |