(să-stro͞o′gə, săs′trə-, sä′strə-) also zas·tru·ga(ză-stro͞o′gə, 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 Indo-European roots.]