BJUI Share definition Flag Pronounced (B-jew-I) The act of giving a blow job while under the influence of alcohol. Guy 1: That chick is such a prude when shes sober.Guy 2: Ya, but she gives a phenomenal BJUI. BJUI by Heaney773 June 2, 2010 0 0 Get merch Get the BJUI mug. Buy Now — $32.95 See more merch