| Acronym | Definition |
|---|
| VSI | Very Short Introductions (book series) |
| VSI | Vision Systems, Inc. |
| VSI | Vinyl Siding Institute |
| VSI | Vertical Speed Indicator |
| VSI | Virtual Switch Instance |
| VSI | Vehicle System Interface |
| VSI | Voltage Source Inverter |
| VSI | Virtual Switch Interface |
| VSI | Voluntary Separation Incentive |
| VSI | Visual Studio Installer (Microsoft) |
| VSI | Vision Systems International |
| VSI | Vertical Shaft Impactor (industrial rock crushing machine type) |
| VSI | Versatile Seismic Imager (Schlumberger tool) |
| VSI | Virtual Socket Interface |
| VSI | Very Seriously Ill |
| VSI | Vertical Scanning Interferometry |
| VSI | Very Seriously Injured |
| VSI | Volontaire de Solidarité Internationale (French: Volunteers for International Solidarity) |
| VSI | Visual Site Inspection (environmental reports) |
| VSI | Vendor Single Interest |
| VSI | VLBI Standard Interface |
| VSI | Virginia Semiconductor, Inc. |
| VSI | Volunteer Sector Initiative |
| VSI | Video Simulation Interface (US NASA) |
| VSI | View Student Information (resource; various locations) |
| VSI | Visual Stability Index (concrete) |
| VSI | Vascular Society of India |
| VSI | Vertical Situation Indicator |
| VSI | Virginia Spine Institute |
| VSI | Virtual Server Infrastructure (database management) |
| VSI | Vegetarian Society of Ireland (est. 1978) |
| VSI | Stalling Speed in a Specified Flight Configuration |
| VSI | Veteran Solutions, Inc. (Upper Marlboro, MD) |
| VSI | Verify Supplier Invoice |
| VSI | Vessel Superintendents (UK) |
| VSI | Virtual Screen Interface |
| VSI | Vertical Scale Indicator |
| VSI | Velocity and Steering Indicator |
| VSI | Vehicle State Interface |
| VSI | Vietnam State Inspectorate |
| VSI | Vendor Single Insurance |