Pl. alluvia, alluviums. [a. L. alluvium neut. of adj. alluvius washed against, f. al- = ad- to + luĕre to wash.] A deposit of earth, sand and other transported matter left by water flowing over land not permanently submerged; chiefly applied to the deposits formed in river valleys and deltas.
1665–6. Phil. Trans., I. 121. Our Earth, where Alluviums are made in some places, and the Sea gains upon the Land in others.
1731. Bailey, Alluvia, little islets thrown up by the violence of the stream.
1803. Syd. Smith, Wks., 1859, I. 53/1. An alluvium gained and preserved from the sea.
1830. Lyell, Princ. Geol., I. 187. The Mississippi, therefore, by the continual shifting of its course, sweeps away, during a great portion of the year, considerable tracts of alluvium which were gradually accumulated by the overflow of former years.
1878. A. C. Ramsay, Phys. Geog., xxviii. 458. The bones of which are found in the old alluvia of rivers.
b. fig.
1850. Kingsley, Alt. Locke, vi. (1876), 66. Out of this book alluvium a hole seemed to have been dug near the fireplace.
1862. Ludlow, Hist. U. S., 281. The tide of emigration … left behind it a sort of alluvium of free-soil principles.
