A bedform is one of a series of hollows and ripples formed in the bed of a river by the flow of water.
An antidune is a bedform found in fluvial envoronments, opposing the direction of flow.
J. H. A. Wijbenga has written: 'Changes in bedform dimensions under unsteady flow conditions in a straight flume'
Wavy layers in rock deposits form due to folding, which occurs under high pressure and high temperatures. The rock layers bend and create the wavy appearance. Not sure if that is what you're looking for Wavy layers can also simply be a bedform within sedimentary rocks - these are called wavy bedding or wavy lamination.
Flood plain clays are considered "massive," a term used to describe clays without a bedform, which is the arrangement of particles of sediment. Clays found in lakes are "laminate," whcih means that they are usuallypretty uniformly thick, and lay flat on the bottom of a body of still water with little to no current.