forty pounder 

A large cannon, typically used during the American Civil War

"But when he put his arm around 'er,
He smiled fierce as a forty pounder..." ~Dixie (song)

forty pounder by Ayy Lmao Alien July 1, 2016

Forty Pounder 

A Canadian term for a 40 oz bottle of liquor. Can also be used as just "a 40" or "40".

Jim: "Can you pick me up a forty pounder of Vodka from the liquor store?"
Michael: "Sure thing!"

Forty Pounder by ArterialSquid December 18, 2016

forty pounder 

A forty pounder is a forty ounce bottle of liquor, generally whiskey, vodka, rum, or other 80 proof stuff.

Matt didn't make it to work cause he got himself deucefaced on a forty pounder.

forty pounder by compa62 November 27, 2010