forepole

[noun fawr-pohl, fohr-; verb fawr-pohl, fohr-]Mining.
noun
  1. Also called spile, spill. any of a number of boards or timbers driven forward on top of a set to protect miners lengthening a tunnel from falling debris.
verb (used with object), fore·poled, fore·pol·ing.
  1. to reinforce (the end of an excavated tunnel) with forepoles.

Origin of forepole

An Americanism dating back to 1870–75; fore- + pole1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018