From Longman Dictionary of Contemporary Englishbarrelbar‧rel1 /ˈbærəl/ ●●○ noun [countable] 1 
DTa large curved container with a flat top and bottom, made of wood or metal, and used for storing beer, wine etc The wine is aged in oak barrels.barrel of barrels of beer2 a unit of measurement for oil, equal to 159 litresbarrel of two million barrels of oil3 PMWthe part of a gun that the bullets are fired through4 → have somebody over a barrel5 → be a barrel of laughs → pork barrel, → scrape (the bottom of) the barrel at scrape1(5), → lock, stock, and barrel at lock2(3)
DTa large curved container with a flat top and bottom, made of wood or metal, and used for storing beer, wine etc The wine is aged in oak barrels.barrel of barrels of beer2 a unit of measurement for oil, equal to 159 litresbarrel of two million barrels of oil3 PMWthe part of a gun that the bullets are fired through4 → have somebody over a barrel5 → be a barrel of laughs → pork barrel, → scrape (the bottom of) the barrel at scrape1(5), → lock, stock, and barrel at lock2(3)Examples from the Corpus
barrel• Thérèse felt her way around a barrel as tall as she was.• The area may contain up to 2 billion barrels of oil.• In late August, after testing the cataract with an empty barrel, he announced that he would go over him-self.• When it snows in Boston, residents litter the streets with old furniture, barrels and a rusty washing machine or two.• Each new barrel costs £1.50; they are normally only used for one race and there are 50 barrels on a raft.• At farmhouse level, cider is hard stuff to control, in the barrel or in the head.• He saw the barrels on the truck and quick-counted more than fifteen.• That morning he had bought a whole barrel of Gunpowder Pepper from one of the human victuallers.barrelbarrel2 verb [intransitive] American English informal FAST/QUICKto move very fast, especially in an uncontrolled way A vehicle barreled out of a shopping center and crashed into the side of my car.→ See Verb tableExamples from the Corpus
barrel• The train barreled down the tracks.• Smith barreled into him, knocking him over.• For barreling into homeroom just as the bell rings.• Instead of swerving right, I swerved left, barreling straight into him with the fender.From Longman Business Dictionarybarrelbar‧rel /ˈbærəl/ noun [countable]1TRANSPORTa large round container with a flat top and bottom, used for storing and carrying liquids such as oil and beerbarrels of beer2an amount of a liquid contained in a barrel, used as unit of measurement, especially in the oil industryThere were fears that the price of crude would drop as far as $15 a barrel.The country produces more than 650,000 barrels per day of crude oil. → see also pork barrelOrigin barrel1 (1200-1300) Old French baril 