Prug Share definition Flag Racial slur: a native of Paraguay. Commonly used in central Canada to refer specifically to immigrants from Paraguay. Geech: Hey Merl, I heard you got new neighbours!Merl: Don't get so excited, they're Prugs. Prug by Cousin Merl November 6, 2010 0 0 Get merch Get the Prug mug. Buy Now — $32.95 See more merch