| Acronym | Definition |
|---|
| TSIS | Technical Support Information Services |
| TSIS | TIES (Technology Information Education Services) Student Information System |
| TSIS | Total Solar Irradiance Sensor (US NASA) |
| TSIS | Training and Simulation Industry Symposium |
| TSIS | Transportable Satellite Internet System |
| TSIS | Transportation Security Intelligence Service |
| TSIS | The Sky I Scrape (Pearl Jam song) |
| TSIS | Tien Shan International School (Almaty, Kazakhstan American education style school) |
| TSIS | Timber Sale Information System (Bureau of Land Management, USDI) |
| TSIS | Talent Scout International School (Vienna, Austria) |
| TSIS | Technical Services Information System |