Alluvial \Al*lu"vi*al\, n. Alluvial soil; specif., in Australia, gold-bearing alluvial soil. [Webster 1913 Suppl.]
Alluvial \Al*lu"vi*al\, a. [Cf. F. alluvial. See {Alluvion}.] Pertaining to, contained in, or composed of, alluvium; relating to the deposits made by flowing water; washed away from one place and deposited in another; as, alluvial soil, mud, accumulations, deposits. [1913 Webster]