wellhole

wellhole englanniksi

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

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

3. {{quote-text|en|year=1846|author=W. M. Buchanan|title=The Dictionary of Science and Technical Terms Used in Philosophy, Literature...

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