| Acronym | Definition |
|---|
| YSI➣Yousendit (File Transfer Website) |
| YSI➣Young Sustainable Impact (Norway) |
| YSI➣Youth Service, Inc. (Philadelphia, PA) |
| YSI➣Yellow Springs Instruments (Yellow Springs, OH) |
| YSI➣You Said It |
| YSI➣Young Social Innovators (Ireland) |
| YSI➣Youth Science Institute |
| YSI➣Young Scots for Independence (Edinburgh, Scotland, UK) |
| YSI➣Youth Sports Institute (various locations) |
| YSI➣You Stupid Idiot |