| Term | Definition |
| Aquifer | an underground layer of permeable rock that contains water |
| Atmosphere | the outer layer of gases of a large body in space |
| Biosphere | all living things on Earth, land, and water. |
| Cryosphere | the frozen layer of Earths surface |
| Condensation | the transfer of heat energy from one substance to another through contact (two objects touching) |
| Convection | the transfer of energy from place to place by the motion of heated gas or liquid in the Earth's mantel |
| Downwelling and Upwelling | when the water moves to different levels of depth due to surface currents |
| Evaporation | process by which liquid water turns to gas (water vapor) |
| Global Wind | wind belt that circles the Earth |
| Ground Water | the water beneath the surface of the ground (consisting mainly of surface water that has seeped down) |
| Hydrosphere | The water on or surrounding the Earth's surface (includes the water of the oceans and atmosphere) |
| Impermeable | Water can't pass through the substance |
| Lithosphere | The crust and upper mantel of the Earth |
| Ocean Current | A mass of moving ocean water |
| Permeability | the ability of water to pass through a porous rock or sediment |
| Pollution | the presence of harmful or poisonous substance in the enviorment |
| Precipitation | process by which water, in any form, falls from the atmosphere to Earth's surface |
| Radiation | energy that travels across distances as certain types of waves |
| Runoff | process of water flowing over the surface of the ground |
| Surface Water | water that collects on the surface of the ground |
| Transpiration | process of water evaporating through the leaves of plants |
| Watershed | The area of land where all the water that is under it or drains off of it goes (it collects to the same place) |
| Water Table | underground surface of soil or rock that is saturated with water |
