Ponto, pontônis, p pro. m. g. Cæs. A whirie bote: a ferie bote.Pon ticus. Vide PONTVS.
Lewis and Short: Latin dictionary
ponto, ōnis, m. [1. pons]. I.A kind of Gallic transport, a punt, Caes. B. C. 3, 29.— II.A floating bridge, a pontoon, Aus. Idyll. 12, 10; Dig. 8, 3, 38; Gell. 10, 25, 5.