Pon-ton' or Pon-tōon', n.

n. [Fr. & Sp. ponton, It. pontone, from Lat. pons, pontis, a bridge.]

1. A light frame-work or float, as of India-rubber cloth, or other material, easily transported, used in forming a bridge quickly for the passage of troops.
2. (Naut.) A low, flat vessel, resembling a barge, furnished with cranes, capstans, and other machinery, used in careening ships, chiefly in the Mediterranean; a lighter.

Ponton-bridge, a bridge formed with pontons. — Ponton-train, the carriages of the pontons, and the materials they carry for making a ponton-bridge. Ponton is said by army engineers to be the more common orthography, and therefore to be preferred to pontoon, the old form. Ponton-bridge. a, side view of ponton; b, end view of pontons, with joists, flooring, and timbers fastened upon flooring to keep it in place; c, plan of pontons;