| Hydrauliköl | hydraulic oil |
| Hydraulik | hydraulics hydraulic system |
| hydraulisch | hydraulic |
| Hydrochinon | hydroquinone |
| hydrophil | hydrophilic |
| Hydra | Hydra Lernaean Hydra |
| Hydrat | hydrate |
| Hydrokultur | hydroponics |
| Hydrologin | hydrologist |
| Hydroxyl | hydroxyl |
| hydro- | hydro- |
| Dehydration | dehydration |
| Hydrant | hydrant fire hydrant fireplug |
| Hydrathülle | hydration shell |
| Hydraulikpresse | Bramah press hydraulic press |
| Hydrid | hydride |
| Hydrologe | hydrologist |
| Hydrologie | hydrology |
| Hydrolyse | hydrolysis |
| Hydroxid | hydroxide |