IPA: /ˈsækfəl/
KK: /ˈsækfəl/
The quantity of something that can fit inside a sack.
He carried a sackful of potatoes from the market.
Sackful → It is formed from "sack" (from Old English *sæc*, meaning a bag or pouch) and "-ful" (meaning full of). The word "sackful" means full of a sack or the amount that a sack can hold.
Think of a 'sack' as a bag that is 'full' — that's why 'sackful' means the amount that fills a sack.