| 1. | the capacity of a merchant vessel, expressed either in units of weight, as deadweight tons, or of volume, as gross tons. |
| 2. | ships collectively considered with reference to their carrying capacity or together with their cargoes. |
| 3. | a duty on ships or boats at so much per ton of cargo or freight, or according to the capacity in tons. |
tonnage
in shipping, the total number of tons registered or carried, or the total carrying capacity.
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