Alluvion

n. alluvium, mud or sand deposited by flowing water; deposits of mud or sand; land formed by deposits of mud or sand; flood

Alluvion a legal term which describes the increase in the area of land due to sediment (alluvium) which is deposited by a river. This changes the size of a piece of land (a process called accession) and thus its value over time.
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Noun
1. gradual formation of new land, by recession of the sea or deposit of sediment
(hypernym) geological process, geologic process
2. the rising of a body of water and its overflowing onto normally dry land; "plains fertilized by annual inundations"
(synonym) flood, inundation, deluge
(hypernym) geological phenomenon
(hyponym) debacle
3. clay or silt or gravel carried by rushing streams and deposited where the stream slows down
(synonym) alluvial sediment, alluvial deposit, alluvium
(hypernym) sediment, deposit
(hyponym) placer
(substance-meronym) alluvial soil

n. alluvion, alluvium, mud or sand deposited by flowing water; deposits of mud or sand; land formed by deposits of mud or sand; flood

n. alluvium, mud or sand deposited by flowing water