knapsack
/ˈnæpsæk/noun
- a soldier's or hiker's bag with shoulder straps, carried on the back, and typically made of canvas or other weatherproof material（士兵或徒步旅行者用的帆布等防水材料做的）背包。
词源
early 17th cent.: from Middle Low German, from Dutch knapzack, probably from German knappen 'to bite' + zak 'sack'.