1. The epic and unparalleled event of taking multiple alcoholic shots, the number of which is significant (ie. years of marriage, number of V-cards taken, etc.), in order to expedite the process of pregaming
. The use of a theme song is highly recommended, though not required.
2. The act of progressing.
"Dood, Timmy just took a 13 shot progression for his frat's 13th anniversary and now he's puking in the bathtub."