noun, plural -dies, verb, -died, -dy⋅ing.| 1. | a current at variance with the main current in a stream of liquid or gas, esp. one having a rotary or whirling motion. |
| 2. | a small whirlpool. |
| 3. | any similar current, as of air, dust, or fog. |
| 4. | a current or trend, as of opinion or events, running counter to the main current. |
| 5. | to move or whirl in eddies. |

ed·dy (ěd'ē) n. pl. ed·dies
v. intr. To move in or as if in an eddy. See Synonyms at turn. v. tr. To cause to move in or as if in an eddy. [Middle English ydy, probably of Scandinavian origin; akin to Old Norse idha.] |
eddy
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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