| Subject | English | Estonian |
| transp., avia., el. | Electrical Wiring Interconnection System | elektriühendus |
| transp., avia., el. | Electrical Wiring Interconnection System | elektrijuhtmestik |
| comp., MS | Open Systems Interconnection model | Open Systems Interconnection (A networking model introduced by the International Organization for Standardization (ISO) to promote multi-vendor interoperability. OSI is a seven-layered conceptual model consisting of the application, presentation, session, transport, network, data-link, and physical layers) |
| commun., comp. | open systems interconnection reference model | avatud süsteemide ühendamise etalonmudel |
| gen. | open systems interconnection reference model | OSI etalonmudel |
| econ. | systems interconnection | süsteemide ühendamine |