• Webster's Revised Unabridged Dictionary
    • n Pontvolant (Mil) A kind of light bridge, used in sieges, for surprising a post or outwork which has but a narrow moat; a flying bridge.
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Century Dictionary and Cyclopedia
    • n pontvolant Milit., a flying-bridge; a kind of bridge used in sieges for surprising a fort or outwork that has but a narrow moat. It is composed of two small bridges laid one above the other, and so contrived that, by the aid of cords and pulleys, the upper one may be pushed forward till it reaches the destined point.
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Webster's Revised Unabridged Dictionary
F. pont, bridge + volant, flying