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Glossary of Terms

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American Great Lakes Ports Association (AGLPA) – The AGLPA represents the 13 public port authorities on the United States side of the Great Lakes. Each of the member port agencies is a division of state or local government, or an independent agency created by state statute. As a group, and individually, Great Lakes ports work to foster maritime commerce in the region and economic development in their communities.

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Ballast Water – When not fully loaded, cargo ships must take on water (ballast) to maintain their stability. Once pumped onboard, ballast water is stored in narrow cavities (ballast tanks) built into the hull of a ship.

Beam – Greatest width of a vessel.

Bulk Cargo – means cargo consisting of goods, loose or in mass, that generally must be shoveled, pumped, blown or scooped in the handling and includes:

  • Cement
  • Coke and petroleum coke
  • Liquids carried in ships’ tanks
  • Ores and minerals, including alumina, bauxite, gravel, phosphate rock, sand, stone and sulphur
  • Scrap metals
  • Raw sugar
  • Woodpulp
  • Grain

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Cabotage Laws – The United States, as well as other nations, protects its domestic transportation industries through cabotage laws. “Cabotage” from the French word “caboter” means to sail coastwise or by the capes – the “capes” being visible points on the shore. U.S. Maritime Cabotage Laws include 31 separate enactments governing the transportation of cargo and passengers between two points in the U.S., its territories and possessions, and all dredging, towing, salvage and other marine operations and fishing in U.S. waters. These laws reserve to U.S.-flagged vessels the right to transport cargo and passengers between U.S. ports. The current cabotage statute for ownership, construction, and crewing of cargo and passengers is the Merchant Marine Act of 1920, often referred to as the Jones Act.

Cargo – All goods aboard a ship whether carried as revenue or non-revenue freight or carried for the ship owner.

Carrier – Any company, or its representative, engaged in physically moving a cargo between an origin and a destination.

Chandler – An individual or company selling equipment and supplies for ships.

Chamber of Marine Commerce (CMC) – The CMC is an Ottawa-based association that represents 150 marine industry stakeholders including major Canadian and American shippers, ports, terminals and marine service providers, as well as domestic and international ship owners. The CMC represents the interest of its members by addressing government issues affecting marine transportation. Advocacy extends to both the federal and provincial levels of government and, when appropriate, to U.S. federal and state governments and agencies.

Closing Date – The date on which both the Montreal-Lake Ontario portion and the Welland Canal portion of the Seaway are closed for vessel traffic.

Coal – A solid, brittle rock, formed by partial to complete decomposition of vegetation. It is the primary fuel used by iron and steel producers. Western coal has been widely used since the mid-1970s due to its lower sulfur content.  A 1,000-foot laker can carry enough coal to produce the electricity needed to power a metropolitan area the size of Greater Detroit for one day.

Coke – Used as a fuel and as a reducing agent in smelting iron ore in a blast furnace. The production of one ton of raw steel requires nearly one ton of coke.

Compartments – The number of holds or sections in the ship; the interior area divided off by bulkheads, such as the “engine compartment.”

Containerized Cargo – Cargo shipped in a container that is enclosed, permanent, reusable, non-disposable and weather tight.

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Depth – a measurement inside the hull from the underside of the deck to the top of the keel; not the same as the “draft.”

Draft – The number of feet that the hull of a ship is beneath the surface of the water.

Dredging – An excavation operation necessary to maintain appropriate water depths for the safe navigation of ships. This activity is usually carried out by scooping or suctioning of sand and mud deposited by water currents into the navigation channels.

Dock – A dock typically consists of the following elements: a shipping channel providing underwater clearance for vessels; a seawall defining the edge between land and water; and land-side improvements such as an outdoor cargo storage area, and/or warehouse buildings providing indoor storage for cargo. Typical equipment at a dock includes cranes to unload ships, conveyor systems to transport bulk cargo, and forklifts to move and stack cargo.

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Freight – Refers to either the cargo carried or the charges assessed for carriage of the cargo.

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General Cargo – Goods other than bulk cargo, grain, government aid cargo, steel slabs and coal.

Grain – A small, hard seed or seedlike fruit; especially that of any cereal plant. Wheat, soybeans and corn are the primary grains moved on the Great Lakes.

Great Lakes/St. Lawrence Seaway System – The navigable waterway stretching from Duluth, Minnesota on the west to the Gulf of St. Lawrence on the east. The system is composed of the five Great Lakes (Superior, Huron, Michigan, Erie and Ontario), their connecting channels, and the St. Lawrence River.

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Harbor – Any place to which ships may resort for shelter, or to load or unload passengers or goods, or to obtain fuel, water, or supplies.

Hatch – The opening in the deck of a vessel that gives access to the cargo hold.

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Iron ore – The primary raw material used in the manufacture of steel. It takes about 1.5 tons of iron ore to make one ton of raw steel.  A 1,000-foot laker can carry enough iron ore to keep a major steel mill in operation for nearly five days.

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Jones Act – A cabotage law that provides that no merchandise transported by water between U.S. ports is to be carried “in any other vessel than a vessel built and documented under the laws of the United States, crewed by Americans, and owned by persons who are citizens of the United States.”

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Keel – The main longitudinal member of the hull; the body of the vessel.

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Laker – A cargo ship designed exclusively for use in the Great lakes –  St. Lawrence Seaway System.

Light loading – A vessel carrying less than a full load.

Limestone – A common sedimentary rock consisting mostly of calcium carbonate. Also referred to as aggregate, which is used as a building stone and in the manufacturing of lime, carbon dioxide, and cement.  For example, one mile of four-lane highway requires 85,000 tons of aggregate as the base.

Longshoreman – Individual employed at a port to load and unload ships.

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Manifest – A detailed summary of the total cargo of a vessel.

Maritime Domain – It is all areas and things of, on, under, relating to, adjacent to, or bordering on a sea, ocean, or other navigable waterway, including all maritime related activities, infrastructure, people, cargo, and vessels and other conveyances.

Metric Ton – 2,204 pounds of a given material.

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Navigation Season – The period corresponding to the first sailing (opening date) and the final lay-up (closing date) of the navigation system, generally late March to late December; however, certain internal segments of the system may operate longer depending on weather and ice conditions.

Net Ton – 2,000 pounds of a given material.

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Opening Date – The earliest date on which either the Montreal-Lake Ontario portion or the Welland Canal portion of the Seaway is opened for vessel traffic. Likewise, the earliest date on which the Soo Locks open for vessel traffic.

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Port – In simple terms, a port is a harbor with piers and docks.  A term that also means the left side of a ship when facing forward.

Port of Call – Port where a ship discharges or receives traffic.

Port of Entry – Port where cargo is unloaded and enters a country.

Port of Exit – Place where cargo is loaded and leaves a country.

Potash – Any of several compounds containing potassium, used chiefly in fertilizers.

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Salt – A while crystalline form of sodium chloride. Salt is mined in Michigan, Ohio and Ontario. Among salt’s more than 14,000 known uses are de-icing, seasoning, and preserving food. On average, a 12,000 ton salt cargo will de-ice approximately 20 miles of two-lane road.

Saltie – An informal term used to refer to ocean-going (saltwater) cargo ships that operate on the Great Lakes – St. Lawrence Seaway System.

Sand – A class of materials called granular matter. Sand is a naturally occurring, finely divided rock. Sand is a major ingredient of mortar, plaster, concrete, and asphalt.

Seawaymax Vessel – The largest vessel that can transit the locks of the St. Lawrence Seaway. Limited by the lock dimensions: Length is 740 feet (226 meters); Beam is 78 feet (24 meters); Draft is 26 feet (7.92 meters).

Self-unloading Technology – Self-unloading vessels can discharge dry bulk cargo without assistance from any shore-side equipment or shore-side personnel. They are capable of transporting and unloading almost any free-flowing, dry bulk commodity, including iron ore, coal, limestone, sand, gypsum, and grain. The cargo is unloaded using a system of conveyors built into the ship. This system carries the cargo up to the main deck of the ship where it is then transferred onto the boom conveyor belt. The boom conveyor can be lifted and swung hydraulically left or right to position the cargo on the dock or into a receiving hopper. This technology can discharge cargo at rates of up to 10,000 tons per hour.

Shipment – The tender of one lot of cargo at one time from one shipper to one consignee on one bill of lading.

Shipper – A company who owns the cargo that is being transported. Also called a Consignor.

Short Sea Shipping – Refers to the practice of adding a waterborne leg to an intermodal shipment that normally would travel by road or rail. The objective is to reduce travel time, avoid congested routes and reduce cost. It also holds out the promise of improving energy efficiency and lowering greenhouse gas emissions.

Starboard – The right side of a ship when facing the bow.

Stern – the end of a vessel; opposite of the bow.

Stevedore – Individual or firm that employs longshoremen and who contracts to load or unload the ship.

Stowage – A marine term referring to loading freight into ships’ holds.

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Transport – To move cargo from one place to another.

Transship – To transfer goods from one mode of transportation to another, or from one ship to another.

Transshipment Port – Place where cargo is transferred to another carrier.

Turnaround – In water transportation, the time it takes between the arrival of a vessel and its departure.

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Vessel Agent – A vessel agent represents a vessel’s Owner or Operator at each U.S. port-of-call, and takes care of the needs of that vessel and its crew while in port. Typically, a vessel arriving from a foreign port has numerous governmental regulatory requirements which must be met. The agent has a working knowledge of each requirement and can help with any vessel operation or need. The agent understands the local culture, rules and conditions, and interfaces with the local government agency representatives, working to make a port call safe, efficient and productive.

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Wharf – A structure built on the shore of a harbor extending into deep water so that vessels may lie alongside.