|—n , pl -dies|
|1.||a movement in a stream of air, water, or other fluid in which the current doubles back on itself causing a miniature whirlwind or whirlpool|
|2.||a deviation from or disturbance in the main trend of thought, life, etc, esp one that is relatively unimportant|
|—vb , -dies, -dies, -dying, -died|
|3.||to move or cause to move against the main current|
|[C15: probably of Scandinavian origin; compare Old Norse itha; related to Old English ed- again, back, Old High German it-]|
fluid current whose flow direction differs from that of the general flow; the motion of the whole fluid is the net result of the movements of the eddies that compose it. Eddies can transfer much more energy and dissolved matter within the fluid than can molecular diffusion in nonturbulent flow because eddies actually mix together large masses of fluid. Flow composed largely of eddies is called turbulent; eddies generally become more numerous as the fluid flow velocity increases. Energy is constantly transferred from large to small eddies until it is dissipated. (See fluid mechanics.)
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