A mass of marijuana smoke pulled into a bottle via the creation of a vacuum (the bottle is often referred to as the polish cow) that yields a tremendous burst of THC to the lungs with a relatively little amount of bud. Underground vernacular in Chicago, originated by a group of UIC students. Similar to shotgunning, but with little to no waste of smoke.
One bottle of polish milk and I was knocked on my ass for hours!
by God's Debris December 31, 2006