• WordNet 3.6
    • n alluvium clay or silt or gravel carried by rushing streams and deposited where the stream slows down
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Webster's Revised Unabridged Dictionary
    • n Alluvium (Geol) Deposits of earth, sand, gravel, and other transported matter, made by rivers, floods, or other causes, upon land not permanently submerged beneath the waters of lakes or seas.
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Century Dictionary and Cyclopedia
    • n alluvium A deposit, usually of mingled sand and mud, resulting from the action of fluviatile currents: applied by geologists to the most recent sedimentary deposits, especially such as occur in the valleys of large rivers: opposed to diluvium (which see). Alluvion (which see) was formerly used for both marine and fresh-water deposits, but alluvium has taken its place, although generally used only for fluviatile deposits.
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Chambers's Twentieth Century Dictionary
    • n Alluvium al-lū′vi-um the mass of water-borne matter deposited by rivers on lower lands
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Webster's Revised Unabridged Dictionary
L., neut. of alluvius,. See Alluvious
Chambers's Twentieth Century Dictionary
L.—alluĕre, to wash to or on—ad, and luĕre = lavāre, to wash.


In literature:

Here and there, dwarf spruce, rooting and grovelling in the shallow alluvium, marked the proximity of the timber line.
"The God of His Fathers" by Jack London
Horner on the alluvium of the Nile, 274.
"The Origin of the World According to Revelation and Science" by John William Dawson
The adjective of alluvium, which see.
"Principles of Geology" by Charles Lyell
And so the alluvium is formed which fills the lower portions of our river valleys.
"The Geological Story of the Isle of Wight" by J. Cecil Hughes
This alluvium consists of gravel firmly cemented with mud and clay, and is unquestionably water-tight.
"The Panama Canal" by J. Saxon Mills
Five mounted Rajputs holding torches led as the convoy started across the sandy alluvium toward the river.
"The Moghul" by Thomas Hoover
Such isolated portions are usually sections of winding subterranean hollows filled up with alluvium.
"A Manual of Elementary Geology" by Charles Lyell
Fairly thick beds of peat are found in the alluvium of the Kennet at Newbury.
"Encyclopaedia Britannica, 11th Edition, Volume 3, Slice 6" by Various
The granite of this round world lies underneath, and the alluvium settles on the surface.
"A New Atmosphere" by Gail Hamilton
They had not sunk a shaft, but were removing the entire alluvium down to bed rock.
"A Claim on Klondyke" by Edward Roper