GEOGRAPHY/Rivers

evaporation

Water changing from liquid to gas

condensation

water vapour cooling into droplets.

precipitation

any form of water falling from the sky as rain, hail, sleet or snow

infiltration

water soaking into soil

percolation

water moving through rock

drainage basin

an area drained by a river and its tributaries

watershed

an imaginary line separating one drainage basin from another

source

where a river begins usually in highland

mouth

where a river ends meeting the sea or a lake

confluence

where do rippers meet

tributary

smaller river joining a larger one

upper course

the highest part of a river

middle course

the middle sections of a river

lower course

the final part of a river