/euh looh"vee euhm/ , n. , pl. alluviums, alluvia /-vee euh/ .
1. a deposit of sand, mud, etc., formed by flowing water.
2. the sedimentary matter deposited thus within recent times, esp. in the valleys of large rivers.
[ 1655-65; alluvius washed against, equiv. to alluv- (see ALLUVION) + -ius, -ium adj. suffix; see -IUM ]