Origin: Ger < dial. form of rücken, the back (see ridge) + sack < OHG sac (see sack)
See rucksack in American Heritage Dictionary 4
Origin: : dialectal Ruck, back (from Middle High German rück, ruck, from Old High German hrukki; see sker-2 in Indo-European roots)
Origin: + Sack, sack (from Middle High German sac, from Old High German, from Latin saccus; see sack1).
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