vauntmure

from The Collaborative International Dictionary of English v.0.48

Vauntmure \Vaunt"mure`\, n. [F. avant-mur. See {Vanguard}, and
   {Mure}.] (Fort.)
   A false wall; a work raised in front of the main wall.
   [Written also {vaimure}, and {vamure}.] --Camden.
   [1913 Webster]