dropshaft

English

Alternative forms

• drop shaft, drop-shaft

Etymology

Compound of drop +‎ shaft.

Noun

dropshaft (plural dropshafts)

1. A vertical shaft which objects can drop through.
   • 1992 April 3, Gary Washburn, “Great Chicago Loop Flood cripples businesses”, in Chicago Tribune‎, archived from the original on 1 January 2023:

     Melas said that district engineers had located Deep Tunnel dropshafts that were near a portion of the freight tunnels and that they would drill, cut or blast through to the flooded areas "as soon as possible."

   • 2006, Maurizio Brocchini, Filippo Trivellato, Vorticity and Turbulence Effects in Fluid Structure Interaction, WIT Press, →ISBN, page 161:

     The water flows from a large suitably fed tank into the dropshaft through a sharp-edged orifice, whose diameter (Do) is 100mm large.

   • 2022 September 12, Patty Wetli, “Chicago Dries Out From Intense Deluge. ‘We Don’t See Rainfall Rates That High’”, in WTTW‎, archived from the original on 10 October 2022:

     The downpour led to some dramatic images of stranded motorists and geysers bursting through manhole covers. The spouts are a rare effect which occurs when too much water rushes into a dropshaft and traps air that’s normally vented.

   • 2023 January 11, Daniel Beekman, “Seattle’s huge sewage tunnel is halfway drilled. Take a look inside”, in The Seattle Times‎, archived from the original on 24 January 2023:

     The gigantic drill that began digging the deep-bore tunnel from Ballard to Wallingford in 2021 passed its halfway mark last month, chewing through soil that gets hauled away to a Ballard drop shaft (a vertical hole that reaches down to the tunneling site from street level) in 25-ton train carloads.

References

• Jesse Sheidlower, editor (2001–2025), “dropshaft, n.”, in Historical Dictionary of Science Fiction.