| Acronym | Definition |
|---|
| ECCO | European Cancer Organisation (Belgium) |
| ECCO | Earth Coincidence Control Office (John C. Lilly) |
| ECCO | Estimating the Circulation and Climate of the Ocean |
| ECCO | European Conference on Clinical Oncology |
| ECCO | Evolution, Complexity and Cognition Group (Belgium) |
| ECCO | European Crohn's and Colitis Organization (Vienna, Austria) |
| ECCO | European Confederation of Conservator-Restorers' Organisation |
| ECCO | Elections Committee of the County of Orange |
| ECCO | East Central Community Organization |
| ECCO | Education Center for Community Organizing (New York, NY) |
| ECCO | Asociación de Ecología Y Conservación (Spanish: Association for Ecology and Conservation; Peru) |
| ECCO | Employee Customer Concerns Office |
| ECCO | Evolutionary Command/Control Operations |
| ECCO | Encinitas Chamber of Commerce Outreach (California) |
| ECCO | European Cannabis Consumers Organisation (founded in Amsterdam, 1994) |
| ECCO | Electronics Controls Company |
| ECCO | Evaluating Capital Creation Options (economics) |