barrel (noun)
1: a tube through which a bullet travels when a gun is fired [syn: gun barrel]
2: a cylindrical container that holds liquids [syn: cask]
3: a bulging cylindrical shape; hollow with flat ends [syn: drum]
4: the quantity that a barrel (of any size) will hold [syn: barrelful]
5: any of various units of capacity; "a barrel of beer is 31 gallons and a barrel of oil is 42 gallons" [syn: bbl] v : put in barrels