| Acronym | Definition |
|---|
| IESI➣Integrated Electronic Standby Instrument (Thales Avionics) |
| IESI➣International Enviroguard Systems, Inc. (Mesquite, TX) |
| IESI➣Independent Environmental Services Incorporated (Haltom City, TX) |
| IESI➣Islamic Education and Services Institute (Chattanooga, TN) |
| IESI➣Information and Electronic Systems Integration Sector (Bae Systems, Inc.) |
| IESI➣Istituto Elaborazioni Segnali ed Immagini (Italian: Institute for Signal and Image Processing; Italian National Research Council) |