drop of the pure Share definition Flag an olde irish term for a glass of whisky. Or in modern days a splash of any strong spirits. Paddy : Lets go and get rat arsed pissed. Murphy : Aye, gives me a guinness and a drop of the pure! drop of the pure by chasedwar March 30, 2012 0 0 Get merch Get the drop of the pure mug. Buy Now — $32.95 See more merch