Oakum - Untwisted fibers of old rope treated with a composition of resin and pitch, used to fill seams of wooden decks.
Category: - Maritime

OBO - A multipurpose ship that can carry ore, heavy dry bulk goods and oil. Although more expensive to build, they ultimately are more economical because they can make return journeys with cargo rather than empty as single-purpose ships often must.
Category: - Maritime - Acronym

OBS - Office of Boating Safety, Canadian Coast Guard
Category: - Maritime - Acronym

Office of Boating Safety - Office of Boating Safety, Canadian Coast Guard
Category: - Maritime

Off-Load - Discharge of cargo from a ship.
Category: - Maritime

OIC - Officer in Charge
Category: - Maritime

Oiler - An unlicensed member of the engine room staff who oils and greases bearings and moving parts of the main engine and auxiliaries. Most of this work is now done automatically and the oiler merely insures it operates correctly.
Category: - Maritime

Oil Record Book - A book or log kept by the master of an oil tanker wherein every discharge or escape of oil is recorded.
Category: - Maritime

Oil Tanker - A ship designed for the carriage of oil in bulk, her cargo space consisting of several or many tanks. Tankers load their cargo by gravity from the shore or by shore pumps and discharge using their own pumps.
Category: - Maritime

Oil Tight - Sealed by welding or caulking to prevent oil leakage.
Category: - Maritime

On Board - To be present on or in the ship.
Category: - Maritime

On Deck - To be present on the upper deck; in the open air.
Category: - Maritime

On-Scene Commander - (OSC) The commander of a search and rescue unit designated to co-ordinate search and rescue operations within a specified search area. "commandant sur place"
Category: - SAR

Open Registry - A term used in place of "flag of convenience" or "flag of necessity" to denote registry in a country which offers favorable tax, regulatory, and other incentives to ship owners from other nations.
Category: - Maritime

Optimization - The procedure or procedures used to make a system or design as effective or functional as possible
Category: - Risk

Ordinal - A level of measurement at which only relative information is available about a feature, such as a ranking. For a highway, for example, the line is coded to show a Jeep trail, a dirt road, a paved road, a state highway, or an interstate highway, in ascending rank.
Category: - GIS

Ordinary Seaman - A deck crew member who is subordinate to the Able Bodied Seamen.
Category: - Maritime

Ore-Bulk-Oil Carrier - A large multi-purpose ship designed to carry cargoes wither of ore or other bulk commodities or oil so as to reduce the time the ship would be in ballast if restricted to one type of commodity. This type of ship is sometimes called bulk-oil carrier.
Category: - Maritime

Ore Carrier - A large ship designed to be used for the carnage of ore. Because of the high density of ore, ore carriers have a relatively high centre of gravity to prevent them being still when at sea, that is, rolling heavily with possible stress to the hull.
Category: - Maritime

Ore-Oil Carrier - A ship designed to carry either ore or oil in bulk.
Category: - Maritime