blunt of a day Share definition Flag cockney rhyming-slang, actually meaning "cunt of a day", ie, bad day. 'blunt' stems from 'james blunt' the musician. I'm really having a blunt of a day, my date didn't put out. blunt of a day by yisaaron May 2, 2008 0 0 Get merch Get the blunt of a day mug. Buy Now — $32.95 See more merch