| Rank | Abbreviation | Meaning |
|---|
| ***** | RAIS | Receive Alarm Indication Signal
| |
| **** | RAIS | Remote Alarm Indication Signal
| |
| **** | RAIS | Reflection Absorption Infrared Spectroscopy
| |
| *** | RAIS | Ram Air Intake System
| |
| ** | RAIS | Regulatory Authority Information System
| |
| ** | RAIS | Redundant Array of Inexpensive Systems
| |
| ** | RAIS | Rescate Ancestral Indígena Salvadoreño
| |
| ** | RAIS | Redundant Array of Inexpensive Servers
| |
| ** | RAIS | Risk Adjustment Impact Study
| |
| ** | RAIS | Retail Access Information System
| |
| ** | RAIS | Risk Assessment Information System
| |
| * | RAIS | Research Administration Information Services
| |
| * | RAIS | Resource Assessment Information Service
| |
| * | RAIS | Redundant Array Integrated System
| |
| * | RAIS | Remote Area Incentive Scheme
| |
| * | RAIS | Relocation Automated Information System
| |
| * | RAIS | RMIT Association of International Students
| |
| * | RAIS | Redundant Array of Independent Systems
| |
| * | RAIS | Rehabilitative Automated Information System
| |
| * | RAIS | Ramkhamheang Adventist International School
| |
| * | RAIS | Research Assistants Industrial Secondments
| |
| * | RAIS | Recyclability Assessment Information System
| |
| * | RAIS | Relatório Anual de Informações Sociais
| |
| * | RAIS | Regional Acidification Information and Simulation
| |
| * | RAIS | rehabilitation automated information system
| |