When you have a bong of some sort and light the weed slowly and let the smoke inside get really smokey to the point where it looks like milk.
1st person: Damn thats a lot of Mu Mu Milk you got there.

2nd person: Ha, yeah i know.

1st: You bout to be blazed as fuck!

2nd: MU MU MILK!!!
by kewoto September 12, 2011
Get the Mu Mu Milk mug.