Source : Webster's Revised Unabridged Dictionary (1913)

Fluvial \Flu"vi*al\, a. [L. fluvialis, from fluvius river, fr.
   fluere to flow: cf.F. fluvial. See {Fluent}.]
   Belonging to rivers; growing or living in streams or ponds;
   as, a fluvial plant.

Source : WordNet®

fluvial
     adj : of or relating to or happening in a river; "fluvial
           deposits"