sas·tru·ga 
(să-strgə, săstrə-, sästrə-) also zas·tru·ga (ză-strgə, zä-)
(să-strgə, săstrə-, sästrə-) also zas·tru·ga (ză-strgə, zä-)n. pl. sas·tru·gi (-gē) also zas·tru·gi
A long wavelike ridge of snow, formed by the wind and found on the polar plains.
[Russian dialectal zastruga : za, beyond + struga, deep place into which one may fall; see sreu- in the Appendix of Indo-European roots.]
sastrugaCastle Rock and Mt. Erebus
Ross Island, Antarctica