Other forms: silted, silting, silts
Silt is very fine soil carried and dropped by water. River silt, silt up, layers of silt.
The particles sit between sand and clay in size, and water carries them until it slows enough to drop them — which is why deltas, floodplains and reservoirs fill with silt. Annual silt deposits made the Nile valley fertile for millennia until the dam stopped them. To silt up is what a channel does when it stops being dredged. Note silty; and that silt is a defined soil grade.
1nounsiltVery fine soil carried and dropped by water.
“When the flood went down, a thick layer of silt covered the fields.”
2verbfillTo fill with such deposits.
“The old harbour silted up, and ships could no longer reach the town.”
silt is a sediment.
Middle English silte is of uncertain origin, possibly related to a verb meaning to filter, possibly to Scandinavian words for a salt marsh. The trail is not clear.
Proto-Indo-European
*sḗh₂l
Middle English
silte
English, today
silt
Built from
From Middle English silte, cilte, cylte, perhaps from Middle English silen "to filter; strain"; equivalent to sile + -t, or cognate with Norwegian and Danish sylt (“salt marsh”), Middle Low German sulte (“salt-marsh”), German Sülze (“meat in aspic”), ultimately from Proto-Germanic sultijō (“salty water; brine”). Related to Old English sealt (“salt”).
Etymology from Wiktionary, CC BY-SA
Practised in Materials & Substances, Rocks & Minerals