prag Share definition Flag A pragmatic (practical) prisoner who allows others to have sex with him in order to gain security or favors. The acronym PRAG probably also stands for Prison Raped Ass Girl. Hey, can I borrow your prag for the night? prag by pixeleyz November 10, 2008 0 0 Get merch Get the prag mug. Buy Now — $32.95 See more merch