Tŭn'nel-pĭt or Tŭn'nel-shāft, n.
n. A pit or shaft sunk from the top of the ground to the level of a tunnel, for drawing up the earth and stones, for ventilation, lighting, and the like.
n. A pit or shaft sunk from the top of the ground to the level of a tunnel, for drawing up the earth and stones, for ventilation, lighting, and the like.