| Term | Definition |
| Forms of water falling from sky | Precipitation |
| Evaporation of water | Transpiration |
| Water running under water | Underground flow |
| Sea | Ocean |
| Water drained under soil | Infiltration |
| Solid changing to gas | Sublimation |
| Flow of water | Runoff |
| Water do this when temperature goes over 100 degree | Evaporation |
| Compress | Condensation |
| Form of crystaline water ice | Snow |
| Under 0 degree water forms this | Ice |
| Flow of underground | Underground flow |
| Flow of the air | Wind |
| Place where it is drained by a river system | Watershed |
| Where no more can be abosrbed | Saturation |
| Layer of rock where water flows | Aquifer |
| Water passing through rock | Permeability |
| Under ground boundary | Water Table |
| Filtering through porous materials | Percolation |
| Water on the surface | Surface water |