사막에서 탁월풍의 방향과 평행하게 형성되는 길고 좁은 형태의 모래 언덕.
A long, narrow sand dune or chain of dunes extending in a direction parallel to that of the prevailing wind.
예문:
"The vast desert landscape was marked by endless rows of saif dunes stretching toward the horizon."
"Geologists study the formation of a saif to understand historical wind patterns in arid regions."