| Acronym | Definition |
|---|
| SOI | Statistics Of Income (IRS) |
| SOI | Silicon-On-Insulator |
| SOI | Southern Oscillation Index (see ENSO) |
| SOI | Statement of Intent |
| SOI | Sphere of Influence |
| SOI | School Of Infantry |
| SOI | Source of Information |
| SOI | Structure of Intellect |
| SOI | Survey Of India |
| SOI | Saturn Orbit Insertion |
| SOI | Special Olympics Inc. |
| SOI | Secretary of the Interior |
| SOI | Sons of Iraq (Sunni tribal group; Iraq) |
| SOI | Sick of It |
| SOI | Solar Oscillations Investigation |
| SOI | Survey of Israel |
| SOI | Sit On It |
| SOI | Start of Image |
| SOI | Signal Of Interest |
| SOI | Signal Operating Instructions |
| SOI | Severity of Illness (medical charting) |
| SOI | Semiconductor on Insulator |
| SOI | Società Orticola Italiana (Italian Horticultural Society) |
| SOI | State of Insanity |
| SOI | Space Object Identification |
| SOI | Summary of Information |
| SOI | Supplier-Owned Inventory |
| SOI | Surgical Orthotopic Implantation |
| SOI | Standard of Identity (bottled water labeling) |
| SoI | Shadows of Isildur (game) |
| SOI | Scamp Owners International |
| SOI | Sensor of Interest |
| SOI | Service Order Input |
| SOI | Signal Operation Instruction(s) |
| SOI | Sea of Insanity (webcomic) |
| SOI | Standard Operating Instruction(s) |
| SOI | Shares on Issue |
| SOI | Standing Operating Instructions |
| SOI | Standard Operator Interface |
| SOI | Share of Ink (public-relations) |
| SOI | State Oceanographic Institute of Roshydromet (Russia) |
| SOI | Source of Impact |
| SOI | Seen or Implied |
| SOI | Syllabus of Instruction |
| SOI | Slipped on Ice (medical; cause of an accident) |
| SOI | Statement of Operating Intent (Canada) |
| SOI | Seeds of Insanity (gamers clan) |
| SOI | Solar Oscillations Imagery |
| SOI | Store Operating Income |
| SOI | System Operating Instruction (how to operate One System, Nuclear Power) |
| SOI | Security Operations Instructions |
| SOI | Student Outreach Intern |
| SOI | Sales Office Identification |
| SOI | Supply Operating Instruction |
| SOI | Selected Opportunistic Infectious |
| SOI | Spinscan Ozone Imager |
| SOI | Standards Organisation of Iran |
| SOI | Switchboard Operating Instruction |
| SOI | Sum of Infeasibilities |
| SOI | Sound of Inevitability (gaming guild) |
| SOI | Shadow of Infinity (trading card game) |
| SOI | Stage of Involvement (software development) |
| SOI | School of Informatics (various locations) |
| SOI | Spreading Odontogenic Infection (dentistry) |
| SOI | Symphony Orchestra Institute (various locations) |