| anthropogenic | originated by humans |
| aquifer | naturally stored underground water |
| Artesian well | a well made by a perpendicular boring into a confined aquifer |
| brackish | having a somewhat salty taste |
| catchment | the physical or surface area from which rainfall flows into a river, lake or reservoir |
| dendritic | "tree branch-like" shape |
| drainage basin | region surrounding a lake, reservoir and rivers from which water is drained into |
| ecosystem | functional natural component consisting of plants, animals, and microorganisms together with the surroundings |
| estuary | the part of the wide lower course of a river where it is met by the sea |
| fauna | animals |
| fjord | a long, narrow, deep inlet of the sea between steep slopes in a coastal area |
| flora | plants |
| hydrologic cycle | cycle of water |
| impoundment | a confined body of water |
| oasis | a green patch of vegetation in dry areas or deserts where water is found on the surface |
| perennial ice | ice in glaciers, high mountains and polar areas which are always present throughout the year |
| permafrost | frozen underground water |
| phytoplankton | a community of microscopic plants found in the majority of surface water-bodies |
| runoff | water which flows on the ground surface after rainfall |
| sedimentation | process in which suspended particles settle to the bottom |
| socioeconomic | of or involving both social and economic factors |
| susbsidence | sinking of the ground |
| subterranean | situated or operating beneath the earth's surface; underground |
| Wadi | a name given in the Arab region to an ephemeral watercourse |
| water quality | a description of how good (adequate) a water is for a particular purpose |
| watershed | either the dividing line between two water catchments or the catchment itself |
| water table | the level below which the ground is completely saturated with water |