Water Cycle: the continuous movement of water between Earth's surface and the air, changing from liquid to gas to liquid Evaporation: the slow changing of a liquid into a gas Condensation: the changing of a gas into a liquid Precipitation: any form of water particles that falls from the atmosphere and reaches the ground (rain, sleet, snow, or hail) Run-off: precipitation that flows across the land's surface or falls into rivers and streams Transpiration: the loss of water through a plant's leaves Groundwater: precipitation that seeps into the ground and is stored in tiny holes, or pores in soil and rocks