forepole

from The Collaborative International Dictionary of English v.0.48

forepole \fore"pole`\ (f[=o]r"p[=o]l`), a. (Mining)
   One of the thick laths or poles driven horizontally ahead on
   top of a set of the main timbering in advancing a level in
   loose ground.

   Syn: spile[4]; spill[2d].
        [RDH]