Word Definition Translation abrasion the action of rubbing a surface hard enough to damage it alluvium soil containing earth and sand left by rivers or floods attrition the wearing down of rock particles by friction bank 1 a raised ares of land along the side of river 2 a long area of land with sloping sides basin 1.a large area of a land from which water flows into a particular river or lake 2.a large area of Earth's surface that is lower than the surrounding area bed 1 the ground at the bottom of a sea or river 2 an area in a river, lake, or sea where there are a lot of plants or animals of a prticular kind bend if a road, river etc. Bends, it changes direction in the shape of a curve boulder a very large rock or piece of stone bounce if a ball or other subject bounces, or if you bounce it, it hits a surface then immediatelly moves away from it break off 1 if you break a piece off something, you remove it from the main part 2 if part of something break off, it becomes separated from the main part break up to break something to make smaller pieces bridge a road, railway, or path that goes over a river, over another road atc, and the structure that supports it burst if something fill with air or water burst, or if you burst it, it breaks suddenly because there is too mucg pressure inside it or against it canyon a long valley with steep sides made of rock cascade a small waterfall cliff confluence a place where two rivers join course the direction in which river flows creek 1 a long narrow area of sea that stretches into the land 2 a narrow stream creep if something such as fire, the sun, or fog creeps somewhere, it moves slowly crop a plant grown for food, usually on a farm cut off cut-offs occur when rivers in flood cut through the neck of land in a meander dam a wall built across the river to stop the water from flowing, especially in order to create a lake or to help to produce electric power deposits divide to separate people or things into smaller groups or parts downstream in the direction that a river or stream is flowing erode to gradually damage the surface of rock or land so that it begins to disappear, or to be gradually damage on this way Rivers estuary the part of a large river where it becomes wide and flows into the sea flood plain a flat area of land near river that often floods when the water level rises floodwater water that is carried over the banks of rivers and streams during a flood and covers previously dry land fluvial realting to the rivers gravel interlocking spur overlapping edges of high ground which interlock in a v-shaped valley and prevent a clear view of river's channel. They project from both sides of a valley jut, jut out to be futher forward than the rest of something levee a wall of soil built along the side of a river to help to prevent it from causing a flood load loop a part of a river where it has eroded a wide curved path i n the shape of the letter S (= meandr) mature fully developed, or fully grown meander 1. if a river or road meanders, it has a lot of turns and curves 2. a part of a river where it has eroded a wide curved path in the shape of a letter S mouth the place where a river is widest and joins the sea obstacle an object that you must remove or go around in order to move forward overhang a part that sticks out from the edge abow something ox-bow lake a curved lake that is formed when a bend in a river becomes separated from the rest of the river plunge to fall quickly from a high position if an amount or level plunges, it suddenly becomes much lower pool a small area of still liquid rapid happening, moving or acting quickly saltation the carrying of particles of soil or sand in the wind or in running water. The particles rise and fall with bouncing movement. sediment a layer of a substance that forms at the bottom of a liquid slope 1 a straight surface that has one end higher than the other 2 the side of a hill or a mountain soft 1 a soft substance is easy to press or shape and is not hard or firm 2 soft water does not containmany natural minerals ansd is easy to use with soap solution a liquid with another substance dissolved in it, so that it has become part of the liquid source the beginning of the river or stream suspension a liquid that contains very small pieces of a solid substances swing traction the action of pulling something over a surface, or the type of power used for pulling tributary a small river that flows into a larger river upstream in the opposite direction to the way that a river or stream flows valley a low area of land between mountains and hills, often with a river flowing through it