[ton.nage] n [in sense 1, fr. ME, fr. MF, fr. tonne tun; in other senses, fr. [1]ton--more at tunnel] (15c) 1: a duty formerly levied on every tun of wine imported into England
2. a: a duty or impost on vessels based on cargo capacity b: a duty on goods per ton transported
3: ships in terms of the total number of tons registered or carried or of their carrying capacity
4. a: the cubical content of a merchant ship in units of 100 cubic feet b: the displacement of a warship
5. a: total weight in tons shipped, carried, or produced b: impressively large amount or weight