hav·er·sack 
(hăvər-săk′)
(hăvər-săk′)n.
A bag carried over one shoulder to transport supplies, as on a hike.
[French havresac, from obsolete German Habersack : German dialectal Haber, oats (from Middle High German habere, from Old High German habaro) + German Sack, bag (from Middle High German sac, from Old High German, from Latin saccus; see SACK1).]