elutriation
elu·tri·a·tion
noun \ē-ˌlü-trē-ˈā-shən\Definition of ELUTRIATION
1
: the removal of substances from a mixture by washing and decanting
2
: the separation of finer lighter particles from coarser heavier particles in a mixture by means of a usually slow upward stream of fluid so that the lighter particles are carried upward
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