The Collaborative International Dictionary of English v.0.48:

Stope \Stope\, n. [Cf. Step, n. & v. i.] (Mining)
   A horizontal working forming one of a series, the working
   faces of which present the appearance of a flight of steps.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Stope \Stope\, v. t. [imp. & p. p. Stoped; p. pr. & vb. n.
   Stoping.] (Mining)
   (a) To excavate in the form of stopes.
   (b) To fill in with rubbish, as a space from which the ore
       has been worked out.
       [1913 Webster] Stope

The Collaborative International Dictionary of English v.0.48:

Stope \Stope\, Stopen \Sto"pen\, p. p. of Step.
   Stepped; gone; advanced. [Obs.]
   [1913 Webster]

         A poor widow, somedeal stope in age.     --Chaucer.
   [1913 Webster]