IPA: /ˈbær.əl.fʊl/
KK: /ˈbɛrəlˌfʊl/
The quantity of something that can fill a barrel, often used to describe a large amount of liquid or other substances.
The farmer filled the tank with a barrelful of water for the crops.
Barrelful → It is formed from "barrel" (from Middle English *barelle*, meaning a cylindrical container) and "-ful" (meaning full of). The word "barrelful" means the amount that a barrel can hold, or full of the contents of a barrel.
Think of a barrel as a cylindrical container that holds liquid, and '-ful' means full of — so a barrelful is the amount that fills a barrel.