tuna cup Share definition Flag A smelly vagina. A Vagina or Pussy that smells like a fish market. "Hey man did you hook up with that chick from the bar?" "Yea, but a bad decision! She had a Tuna Cup!" tuna cup by MikeyCigar October 8, 2013 0 0 Get merch Get the tuna cup mug. Buy Now — $32.95 See more merch