From Longman Dictionary of Contemporary Englishalluviumal‧lu‧vi‧um /əˈluːviəm/ noun [uncountable] technical SGsoil left by rivers, lakes, floods etc
Examples from the Corpus
alluvium• The soils are developed on marine or estuarine alluvium found between the normal high-water mark and the limit of highest spring tides.• The soils are developed on freshwater alluvium.• Using open cut excavation where possible, Nuttall has moved about 26,000 cu m of alluvium and gravel.• Usually floodplains are not veneers of alluvium explicable by lateral channel movements, but considerable thicknesses smoothing over more complex relief.Origin alluvium (1600-1700) Late Latin Latin alluere, from ad- “against” + lavare “to wash” 