'Sap roller' definitions:

Definition of 'Sap roller'

From: GCIDE
  • Sap \Sap\, n. (Mil.) A narrow ditch or trench made from the foremost parallel toward the glacis or covert way of a besieged place by digging under cover of gabions, etc. [1913 Webster]
  • Sap fagot (Mil.), a fascine about three feet long, used in sapping, to close the crevices between the gabions before the parapet is made.
  • Sap roller (Mil.), a large gabion, six or seven feet long, filled with fascines, which the sapper sometimes rolls along before him for protection from the fire of an enemy. [1913 Webster]