hav ‧ er ‧ sack /ˈhævəsæk $ -ər-/ BrE AmE noun [countable]
[ Date: 1700-1800 ; Language: French ; Origin: havresac , from German habersack , from haber 'oats' + sack 'bag' ]
British English old-fashioned a bag that you carry on your back SYN backpack, rucksack