What does rillet mean? a sand dune

a very small stream

What does llano mean? a wooded area

a treeless grassy plain

What does tableland mean? a valley

a plateau

What does adret mean? a mountain slope that receives little sunshine

a mountain slope that faces the sun

What does vale mean? a valley

a plateau

What does hogback mean? a long mountain ridge with steep sides

a low ridge of sand

What does erg mean? a deep inlet between high cliffs

an area of shifting sand dunes

What does oasis mean? a fertile spot in a desert

a low ridge of sand

What does khor mean? a narrow strip of land with sea on either side

a dry watercourse or ravine

What does sowback mean? a low ridge of sand

a long mountain ridge with steep sides