Is another name for a Poop Chute or ones Anus. Often heard being muttered by Sandy or Paddy G in conversations with 'innocent' Birds around from the night before. Also commonly used when reaching in 20+ knots of wind, in fireflies, while in a winning 1,2 position in team racing on Dublin Bay.
Man I just dropped a load through my Shit Shaft. I fucced that bird in the shit shaft last night