| Rank | Abbreviation | Meaning |
|---|
| ***** | RISS | Regular Insulin Sliding Scale
| |
| **** | RISS | Real-Time IR/EO Scene Simulator
| |
| **** | RISS | Rectal Injury Scaling System
| |
| **** | RISS | Revised Injury Severity Score
| |
| *** | RISS | Regional Information Sharing System
| |
| *** | RISS | Reference Information Storage System
| |
| *** | RISS | Regulatory Information Submission System
| |
| *** | RISS | Rhode Island Soft Systems
| |
| *** | RISS | Research Infrastructure Support Services
| |
| *** | RISS | Real-Time Infrared Scene Simulator
| |
| ** | RISS | Research Institute of Science for Safety and Sustainability
| |
| ** | RISS | Research Institute for Social Sciences
| |
| ** | RISS | Roofing Information Support System
| |
| ** | RISS | russian information support service
| |
| ** | RISS | Range Instrumentation and Support System
| |
| ** | RISS | Recon, Isolate, Secure a Foothold, Seize Objective
| |
| * | RISS | Romania Internet Security Systems
| |
| * | RISS | Radiology Information Systems
| |
| * | RISS | Radiology Imaging Systems Specialist
| |
| * | RISS | Relational Interaction Satisfaction Scale
| |
| * | RISS | Real-Time Infrared/Electro-Optic Scene Simulator
| |
| * | RISS | Reference Information Services Section
| |
| * | RISS | Regional Intelligence System Support
| |
| * | RISS | Rural Injury Surveillance Study
| |
| * | RISS | Register of Independent Schools
| |