| Rank | Abbreviation | Meaning |
|---|
| ***** | RISA | retrosigmoid intradural suprameatal approach
| |
| ***** | RISA | Responsibility and Independence Scale for Adolescents
| |
| **** | RISA | Research Initiative on Small Arms
| |
| **** | RISA | Rapid Interactive Structural Analysis
| |
| **** | RISA | ribosomal intergenic spacer analysis
| |
| *** | RISA | radioactive iodine serum albumin
| |
| ** | RISA | Reduced Instruction Set Architecture
| |
| * | RISA | Religion in South Asia
| |
| * | RISA | 131I-radioiodinated human serum albumin
| |
| * | RISA | Russian International Studies Association
| |
| * | RISA | Rome International Schools Association
| |
| * | RISA | Recording Industry of South Africa
| |
| * | RISA | Rhode Island Soccer Association
| |
| * | RISA | radioactive iodinated I125 serum albumin
| |
| * | RISA | radioiodinated human serum albumin
| |
| * | RISA | Radioimmunosorbent Assay
| |
| * | RISA | Research and Innovation Support Agency
| |
| * | RISA | Recording Industry of SA
| |
| * | RISA | Reflux Infants Support Association
| |
| * | RISA | Radioactive Iodinated Serum Albumin
| |
| * | RISA | radio-iodinated human serum albumin
| |
| * | RISA | Rapid Imaging Spectrophotometric Array
| |
| * | RISA | rDNA Internal Spacer Analysis
| |
| * | RISA | radiometric immunosorbent assay
| |
| * | RISA | Regional Infrastructure for Sustaining Agriculture
| |