| Term | Definition |
| Water Cycle | The movement of water through Earth's spheres. |
| evaporation | Heat energy from the sun changes water from a liquid to a gas. The water vapor travels from a body of water on the surface of the Earth to the atmosphere. |
| transpiration | Groundwater travels up the roots and stem of the plant and out tiny holes in the leaves. |
| condensation | This part of the water cycle creates clouds. Cool temperatures cause water vapor (gas) to change into liquid droplets. |
| Precipitation | Water that falls to Earth as rain, snow, hail, or sleet. |
| Runoff | When rain flows along the surface of the Earth into large bodies of water. |
| Infiltration | When water trickles into the ground. |