wellhole

井道; 井底水仓; 垂直大炮眼; 井筒

词形变化

wellholes 复数 wellholes

释义与例句

n.
  1. 1.

    The open space in a floor, to accommodate a staircase.

  2. 2.

    The open space left beyond the ends of the steps of a staircase.

  3. 3.

    A cavity which receives a counterbalancing weight in certain mechanical contrivances, and is adapted also for other purposes.

词源

From well + hole.

来源：wiktionary