mash it up nah Share definition Flag A trinidadian phrase to usually said AFTER some one comes close to breaking something,it is a form of sarcasm. person 1) knocks over appliance Person 2) well mash it up nah..... mash it up nah by bronte91 January 31, 2009 0 0 Get merch Get the mash it up nah mug. Buy Now — $32.95 See more merch