meander

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meander The sinuous trace of a stream channel whose length is normally equal to or greater than 1.5 times the down-valley (or straight-line) distance. It is best developed in cohesive flood-plainalluvium. The relationships between its geometric properties vary little with size: e.g. meander wavelength (the straight-line distance between two points at similar positions (e.g. outward extremities of curve) on two successive curves along the trace) is normally 10–14 times the channel width, irrespective of size. Meander origin is uncertain, but the sinuous curve may be that shape best fitted for the transfer of channelled flow in accordance with the least-work principle. Over time, a meander may move laterally and/or vertically. The process of sideways movement is known as ‘meander migration’; it involves the deposition of point bars on the inner sides of bends and erosion on the outer, and is limited to a tract of flood-plain called the ‘meander belt’. The migration of two adjacent, concave bands may narrow the flood-plain between them, and the restriction is a ‘meander neck’. This widens out to form a bulbous feature, the ‘meander core’, around which the river swings. The surface of a core may show ‘meander scrolls’, which are low, curved ridges of relatively coarse material lying parallel to the main channel and deposited by the stream. An ‘incised meander’ results from down-cutting, and two types are found. (a)If incision is fairly slow, and sideways movement occurs, the result is an ‘ingrown meander’; the slope down which the stream has migrated during incision is called a ‘slip-off slope’.(b)When incision is rapid, with mainly vertical erosion, the consequence is an ‘entrenched meander’.

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meander The sinuous trace of a stream channel whose length is normally equal to or greater than 1.5 times the down-valley (or straight-line) distance. It is best developed in cohesive floodplain alluvium. The relationships between its geometric properties vary little with size: e.g. meander wave-length (the straight-line distance between two points at similar positions (e.g. outward extremities of curve) on two successive curves along the trace) is normally 10–14 times the channel width, irrespective of size. Meander origin is uncertain, but the sinuous curve may be that shape best fitted for the transfer of channelled flow in accordance with the least work principle. Over time, a meander may move laterally and/or vertically. The process of sideways movement is known as ‘meander migration’; it involves the deposition of point bars on the inner sides of bends and erosion on the outer, and is limited to a tract of floodplain called the ‘meander belt’. The migration of two adjacent, concave bands may narrow the floodplain between them, and the restriction is a ‘meander neck’. This widens out to form a bulbous feature, the ‘meander core’, around which the river swings. The surface of a core may show ‘meander scrolls’, which are low, curved ridges of relatively coarse material lying parallel to the main channel and deposited by the stream. An ‘incised meander’ results from downcutting, and two types are found. (a) If incision is fairly slow, and sideways movement occurs, the result is an ‘ingrown meander’. The slope down which the stream has migrated during incision is called a ‘slip-off slope’. (b) When incision is rapid, with mainly vertical erosion, the consequence is an ‘entrenched meander’.

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me·an·der / mēˈandər/ • v. [intr.] (of a river or road) follow a winding course: a river that meandered gently through a meadow | [as adj.] (meandering) a meandering lane. ∎  (of a person) wander at random: kids meandered in and out. ∎  [intr.] (of a speaker or text) proceed aimlessly or with little purpose: a stylish offbeat thriller which occasionally meanders. • n. (usu. meanders) a winding curve or bend of a river or road: the river flows in sweeping meanders. ∎  [in sing.] a circuitous journey, esp. an aimless one: a leisurely meander around the twisting coastline road. ∎  an ornamental pattern of winding or interlocking lines, e.g., in a mosaic.

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meanderadder, bladder, khaddar, ladder, madder •Esmeralda, Valda •scaffolder • lambda •Amanda, Aranda, Baganda, Banda, brander, candour (US candor), coriander, dander, expander, gander, germander, goosander, jacaranda, Leander, Luanda, Lysander, meander, memoranda, Menander, Miranda, oleander, panda, pander, philander, propaganda, Rwanda, sander, Skanda, stander, Uganda, understander, Vanda, veranda, withstander, zander •backhander • Laplander • stepladder •inlander • outlander • Netherlander •overlander • gerrymander •pomander •calamander, salamander •bystander •ardour (US ardor), armada, Bader, cadre, carder, cicada, Dalriada, enchilada, Garda, gelada, Granada, Haggadah, Hamada, intifada, lambada, larder, Masada, Nevada, panada, piña colada, pousada, promenader, retarder, Scheherazade, Theravada, Torquemada, tostada •Alexander, commander, demander, Lahnda, slander •Pravda • autostrada

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meander. Band-like progressive ornament composed of straight lines joining at right angles or cut diagonally (as in the fret and key patterns), or curving (as in the Vitruvian scroll, running-dog, or wave-scroll). It is used on friezes, string-courses, etc.

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meander Naturally occurring looplike bend of a river or stream channel. Meanders form on a flood plain where there is little resistance in the alluvium. They lengthen the river, thus reducing its gradient and velocity. Meanders migrate slowly downstream, depositing sediment on one bank while eroding the opposite. Sometimes meanders make complete loops that, when cut off, form oxbow lakes.

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meander (pl.) windings (of a river, a maze), † intricacies (of affairs) XVI; circuitous course XVII. — (partly through F. méandre) L. mæander — Gr. maiandros, appellative use of the name of a river in Phrygia famous for its notoriously winding course.
Hence vb. XVII.