boyau /bwoˈyō, bwäˈyō or boiˈō/ (fortification)

A communication trench

• twin-born
• twin brother
• twin brothers
• twin-cam
• twin crystal
• twin crystals
• twine
• twined
• twin-engined
• twiner
• twiners
• twines
• twinflower
• twinflowers
• twinge
• twinged
• twinges
• twinging
• twinier
• twiniest
• twi-night
• twi-nighter
• twining
• twiningly
• twining plant