| Hydrolyse | hydrolysis |
| Hydrologe | hydrologist |
| Pyrolyse | pyrolysis |
| Hydroxyl | hydroxyl |
| Hydrologie | hydrology |
| Hydronym | hydronym |
| Hydronymie | hydronymy |
| Heterolyse | heterolysis |
| Hämolyse | hemolysis |
| Homolyse | homolysis |
| Hydrogen | hydrogen |
| Hydrogenase | hydrogenase |
| Hydrologin | hydrologist |
| hydro- | hydro- |
| Hydrometer | hydrometer |
| Hydroxid | hydroxide |
| hydrophil | hydrophilic |
| hydrophob | hydrophobic |
| Mydriase | mydriasis |
| Androloge | andrologist |