Blowin it up! Share definition Flag Takin a shit, defecating, pooping, etc. Man 1: what took you so long? Man 2: I just ate Mexican, and was blowin it up! Man 1: gross! Blowin it up! by Thathuy November 21, 2009 0 0 Get merch Get the Blowin it up! mug. Buy Now — $32.95 See more merch