(pronounced like the first syllable in 'open') A massive joint, spliff, doobie, blunt, or other, preferably rolled as cone, containing some combination of weed/hash and opium.
"Yo dog, roll up a fat op cannon"
A: "Damn yo, I'm fuckin faded, whats in this?"
B: "Damn straight yo, you're puffin on an op cannon"
A: "wooorrrddd..."
A: "Damn yo, I'm fuckin faded, whats in this?"
B: "Damn straight yo, you're puffin on an op cannon"
A: "wooorrrddd..."
by pumpkineater February 24, 2014

1-A person who has ascertained a position of such high douchebaggery that he takes douchbaginess to a new level to totally blow you away with the inability to respond or act for some time.
"After reaming me for several hours on monday about my TPS reports and making me work late every day of the week, my Douche Cannon of a boss made me work on saturday as well!
I think I'll just not come to work anymore."
I think I'll just not come to work anymore."
by Caseofthemondays December 22, 2010

A powerful shoulder cannon used by the predator, it fires blue raspberry cotton blasts with explosive results.
(The predator fired the cotton cannon launching blue raspberry shit at a marine causing him to explode into a bitch torso.
by Bond of Blood December 26, 2010

by shifty hobo November 30, 2017

by Man a boasty. December 2, 2021

dude, you are such a fag, you are staring at the flesh cannon in that porn video.
I wanna shoot guns. Wanna shoot my flesh cannon.
My flesh cannon blew DNA all over that hookers face.
I wanna shoot guns. Wanna shoot my flesh cannon.
My flesh cannon blew DNA all over that hookers face.
by DT105CF May 30, 2013

by billythesnipe June 15, 2003
