B-Day BJ Share definition Flag A complementary Blow Job received to celebrate a man's day of birth. "It's January 25th, bitch. You know what that means: a B-day BJ for me...fo' free" B-Day BJ by chesterchaps September 16, 2009 0 0 Get merch Get the B-Day BJ mug. Buy Now — $32.95 See more merch