Wind-driven sandhill (4)
I believe the answer is:
dune
(Other definitions for dune that I've seen before include "Sandhill" , "Mound of drifted sand" , "Ridge of wind-blown sand" , "Seashore sand hill" , "Coastal sand hill" .)
I believe the answer is:
dune
(Other definitions for dune that I've seen before include "Sandhill" , "Mound of drifted sand" , "Ridge of wind-blown sand" , "Seashore sand hill" , "Coastal sand hill" .)