from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. In military fortification, a trench or ditch covered with a parapet that provides communication between two trenches, particularly the rear and front lines. Boyaus were typically constructed in a zigzag pattern to prevent exposure to direct enemy fire from the front.
- n. A line, drawn winding about, in order to enclose several tracts of land, or to attack some works.
from the GNU version of the Collaborative International Dictionary of English
- n. A winding or zigzag trench forming a path or communication from one siegework to another, to a magazine, etc.
from The Century Dictionary and Cyclopedia
- n. In fort, a ditch covered with a parapet, serving as a means of communication between two trenches, especially between the first and third parallels. Also called a zigzag or an approach.
From French. (Wiktionary)