Definition of Alluvion

Noun: alluvion u'loo-vee-un

Gradual formation of new land, by recession of the sea or deposit of sediment
The rising of a body of water and its overflowing onto normally dry land
"plains fertilized by annual alluvions";
- flood, inundation, deluge
Clay, silt or gravel carried by rushing streams and deposited where the stream slows down
- alluvial sediment, alluvial deposit, alluvium