| Subject | German | English |
| earth.sc., mech.eng. | druckregelndes Hydro-Servoventil | pressure control hydraulic servo-valve |
| energ.ind., chem., polit. | Euro-Quebec-Hydro-Wasserstoff-Projekt | Euro-Quebec Hydro-Hydrogen project |
| energ.ind., chem., polit. | Euro-Quebec-Hydro-Wasserstoff-Projekt | Euro-Quebec Hydro-Hydrogen Production Project |
| health. | hydro-elektrisches Bad | hydroelectric bath |
| health. | hydro-elektrisches Bad | hydro-electric bath |
| min.prod., energ.ind., mining. | Hydro-Frac-Verfahren | fracing |
| min.prod., energ.ind., mining. | Hydro-Frac-Verfahren | hydro-frac |
| min.prod., energ.ind., mining. | Hydro-Frac-Verfahren | hydrofracking |
| min.prod., energ.ind., mining. | Hydro-Frac-Verfahren | hydro-fracturing |
| min.prod., energ.ind., mining. | Hydro-Frac-Verfahren | hydraulic fracturing |
| min.prod., energ.ind., mining. | Hydro-Frac-Verfahren | fracking |
| life.sc. | Hydro-Isohypse | pressure surface contour |
| life.sc. | Hydro-Isohypse | isopiestic line |
| mech.eng. | Hydro-Kompaktgetriebe | hydraulic variable speed drive unit |
| gear.tr., auto. | Hydro-Lenkgetriebe | hydraulic steering |
| transp. | hydro-mechanisches Getriebe | hydro-mechanical transmission |
| mech.eng. | Hydro-Motorblock | hydraulic motor assemblies |
| energ.ind., mech.eng. | hydro-pneumatische Belfast-Boje | hydro-pneumatic wave power device |
| energ.ind., mech.eng. | hydro-pneumatische Belfast-Boje | hydro-pneumatic device |
| energ.ind., mech.eng. | hydro-pneumatische Belfast-Boje | Belfast device |
| transp. | hydro-pneumatische Einheit | hydro-pneumatic power unit |
| earth.sc., mech.eng. | Hydro-Pumpe mit veränderlicher Leistung | variable output pump |
| earth.sc., mech.eng. | Hydro-Pumpe mit veränderlicher Leistung | variable stroke pump |
| earth.sc., mech.eng. | Hydro-Pumpe mit veränderlicher Leistung | variable delivery pump |
| chem., el. | Hydro-Retortenschwelverfahren | hydrotorting process |
| engin. | Hydro-Rollenstößel | hydraulic roller tappet |
| auto. | Hydro-Servolenkung | hydro power steering |
| mech.eng. | Hydro-Servoventil | hydraulic servo-valve |
| construct. | Hydro Vibration | hydrovibration |
| construct. | Hydro Vibration des Bodens | hydrovibrational soil compaction |
| earth.sc., mech.eng. | stromregelndes Hydro-Servoventil | flow control hydraulic servo-valve |
| health. | Tetra-hydro-imidazol | tetra-hydro-imidazole |
| chem. | Tetra-hydro-imidazol | imidazolthiazole |