Dunes Walk Slowly Across the Desert
A dune is a hill of wind-blown sand. Many of them move steadily downwind, year after year.
A dune is a hill or ridge of sand shaped by the wind. Dunes migrate: sand is blown up the gentle windward slope, tips over the crest and slides down the steep lee face, so the whole hill creeps downwind while keeping its shape. Some advance more than ten metres a year, burying roads and buildings in their path. The word came into English from Dutch, and is the same root as *down* in the South Downs, meaning a low hill.
- A sand hill. *A coastal dune.*
- Barchan — a crescent dune. *A barchan.*
- Slipface — the steep lee side. *The slipface.*
- Down — the same root. *The Downs.*
- Dutch — *duin*. *The source.*
Word forms
| Form | Word | Example |
|---|---|---|
| Noun | dune | A dune. |
| Plural | dunes | Dunes. |
| Adjective | duny | Duny. |
| Related | down | A down. |
| Dutch | duin | A dune. |
- Dunes lined the shore.Coast.
- The dune moves each year.Movement.
- Duin is Dutch for dune.Etymology.
How a dune moves
- Wind carries sand up the gentle windward slope
- Grains tip over the crest and slide down the steep lee face
- The shape stays constant while the position shifts
- Some dunes advance more than ten metres a year
- Planting grasses is the usual way to anchor them
Old French *dune*, from Middle Dutch *dune*, related to Old English *dun*, a hill.
Do sand dunes really move?
Yes. Sand blows up the gentle side and slides down the steep side, so the dune creeps downwind while keeping its shape.
Are dune and down related?
Yes. Both come from a root meaning a hill, which is why the South Downs carry the same word.