| Acronym | Definition |
|---|
| ESSI | Education Statistics Services Institute |
| ESSI | Ecole Supérieure en Sciences Informatiques (French) |
| ESSI | Engineered Support Systems Inc. |
| ESSI | Earth Search Sciences Inc |
| ESSI | European Systems and Software Initiative |
| ESSI | European Semantic Systems Initiative |
| ESSI | European Software and Systems Initiative |
| ESSI | Eon Silicon Solution Inc |
| ESSI | Eco Soil Systems Inc. |
| ESSI | European Strategic Safety Initiative (aviation safety partnership) |
| ESSI | Enhanced Synchronous Serial Interface |
| ESSI | Executive Security Services International (Canada) |
| ESSI | Entrepreneurial Style & Success Indicator |
| ESSI | Environmental and Social Sustainability Initiative |
| ESSI | Education, Socialisation, Subjectivation, Institution |
| ESSI | Economic Software Systems International |
| ESSI | Enterprise System Solutions Inc. |
| ESSI | Electronic Security Services, Inc. (est. 1981) |
| ESSI | Envisat and Sea Ice (Conditions in the Baltic Sea) |
| ESSI | Electrospec Sales Inc. |
| ESSI | Enhanced Special Structural Inspection (aviation) |
| ESSI | Estonian-Swedish Suicidology Institute |
| ESSI | Education Service for the Sensory Impaired (UK) |
| ESSI | Extreme Sports Supply International |
| ESSI | Ergonomic & Safety Services Inc (Massachusetts) |
| ESSI | Envirosystems Supply, Inc |
| ESSI | Electronic System Services Incorporated |
| ESSI | Entrepreneurial Spirit and Service Through Innovation (San Francisco, CA) |