tonnage
/'tʌnidʤ/
Học thuậtThân thiện
Definition
Noun: 1. The carrying capacity of a ship, measured in tons: This is the primary meaning, referring to the total weight a ship can carry, including cargo, fuel, passengers, and crew. It is a measure of the ship's size and volume. 2. A duty, tax, or charge based on a ship's carrying capacity: Historically, this refers to a tax levied on ships, especially for entering a port or using a canal, calculated according to the ship's tonnage.
Usage
- Tonnage is used to describe the size and capacity of commercial vessels, such as cargo ships, tankers, and container ships.
- It is a standard unit in maritime law, shipping regulations, and port operations.
- When referring to tax, it is often used in historical or specific legal contexts.
Examples
- Noun (Capacity):
- The new container ship has a gross tonnage of over 200,000 tons.
- Ports have depth restrictions based on the tonnage of vessels they can accommodate.
- Noun (Tax/Duty):
- In the 19th century, nations often collected tonnage duties from foreign vessels.
- The law imposed a tonnage tax on all commercial ships using the canal.
Advanced Usage
- Gross Tonnage (GT): A dimensionless index calculated from the total enclosed volume of a ship. It represents the ship's overall size, not its weight.
- Net Tonnage (NT): A calculated index representing the volume of cargo spaces. It indicates the ship's revenue-earning capacity.
- Deadweight Tonnage (DWT): The total weight a ship can carry (cargo, fuel, supplies, etc.) when submerged to its maximum safe draft. This is the actual weight-carrying capacity.
- Lightweight Tonnage: The weight of the ship itself, including its machinery but excluding any cargo, fuel, or crew.
Variants and Related Words
- Tonnage Dues: Another term for taxes or fees based on a ship's tonnage.
- Tonnage Measurement: The process of calculating a ship's tonnage.
Synonyms
- Burden (archaic, for capacity).
- Duty or tax (when referring to the charge).
- Capacity or displacement (related concepts in shipping).
Related Phrases
- To register a certain tonnage: To be officially measured and documented as having a specific capacity.
- The vessel registers a tonnage of 50,000 DWT.
- Tonnage clause: A provision in a charter party or contract relating to the ship's carrying capacity.
Noun
- a tax imposed on ships that enter the US; based on the tonnage of the ship