sastruga: [sas-truh-guh, sa-stroo-guh]
plural- sastrugi: [sas-truh-gee, sa-stroo-gee]
Noun: Usually used as plural. Sastrugi are wavelike ridges that are sculpted in snowfields by the wind.
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Origin: First known use, 1830-1840. (etymology courtesy of dictionary.com) German < dialectal Russian zastrúga, noun derivative ofzastrugátʾ, zastrogátʾ to plane, shave down (wood), equivalent to za-perfective v. prefix + strugátʾ, strogátʾ to plane, smooth (wood)