Abbreviations & Definitions
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Ton (of 1000 kilos) or Tropical (loadline) 
T&E  Transportation and Exportation: Customs form used to control cargo movement from port of entry to port of exit, meaning that the cargo is moving from one country, through the United States, to another country. 
T&P  Theft (petty) and Pilferage 
T/C  Time Charter 
T/C or TC  Time charter 
T/L  Total Loss 
T/L  Total loss 
T/P  Trans Pacific 
T/S  Time Sheet or Transshipment 
TA  Tanks or Transatlantic 
TAC  Transatlantic Carrier Association 
TAED  Tetraacetylethylenediamine. See Ethyleneamine 
TAFHEX  Thursday afternoons Fridays and holidays excepted 
Tail  Rear of a container or trailer–opposite the front or nose. 
Tail  A protraction at the end of a feedstock or product's distillation curve. A wide spread between the 95 percent point and final boiling point of a stream. A heavy contaminant in a product. Less than ideal distillation can produce tails. 
Tainting  Refers to a substance which is known to be taken up by marine organisms with the result that it is tainted and rendered unpalatable as seafood. Examples are chlorophenols. A taint is defined as "a foreign flavor or odor in the organisms induced by conditions in the water to which the organisms are exposed".  
Taken Aback  A dangerous situation where the wind is on the wrong side of the sails pressing them back against the mast and forcing the ship astern. Most often this was caused by an inattentive helmsman who had allowed the ship to head up into the wind. 
Taking turns  Changing watches with the turn of the hour glass. 
Taking wind out of his sails  Sailing in a manner so as to steal or divert wind from another ship's sails. 
Tall Oil  A by-product of the sulphite digestion of wood pulp for kraft paper manufacture. Tall oil is not a true fat or oil but consists of a natural mixture of 45 percent each of rosin acids and fatty acids and 10 percent unsaponifiable matter. The fatty acids are primarily oleic, linoleic, and linolenic acid. 
Tallow  The rendered fat obtained mainly from beef carcass trimmings from the slaughter house. Some sheep fat may be included in commercial tallow, particularly in Australia and New Zealand. Tallow may be of edible or inedible quality. The latter is derived from lower quality raw materials. Inedible tallow is sold in a number of quality grades and is widely used in soap manufacture and as a source of fatty acids for the oleochemicals industry. 
Tallyman  Controls the cargo going into and out of the vessel. Checks that volume and number tallies with the manifests 
TAME  Tertiary-Amyl-Methyl-Ether 
Tank Barge  Tank barges transport liquid cargoes like petroleum, petrochemicals and liquid fertilizers. Tank barges contain one or many tank compartments below deck with regulated temperature and pressure, depending on the cargo. Tank barges have special safety and security requirements. By the year 2015, all tank barges must be double-hulled. 
Tank Cleaning Vessel  A vessel equipped to clean the tanks of other vessels and remove and transport slops 
Tank Landing Craft  A combat vessel with strengthened bow ro-ro ramp for loading and discharge of tanks and other military vehicles 
Tank Vessel (Tanker)  Ships which carry liquid products, such as crude petroleum, petroleum product, chemicals, liquid natural gas and molasses. 
Tanker  A popular name for the tankships which carry bulk oil, oil products, chemicals, and other liquids in some cases. 
Tanker  A seagoing vessel capable of carrying oil, gas or chemicals in bulk, whether it be a barge or ship. 
Tanker (unspecified)  A tanker whose cargo is unspecified 
Tankers  Ships fitted with tanks to carry liquid bulk cargo such as: crude petroleum and petroleum products, chemicals, Liquefied gasses (LNG and LPG), wine, molasses, and similar product tankers. 
Tare Weight  In railcar or container shipments, the weight of the empty railcar or empty container. 
TARPS  Tarpaulins 
TARV  Trans atlantic round voyage 
TARV (TA R/V)  Trans Atlantic Round Voyage 
Taste  A subjective quality characteristic. It is not defined unambiguously and is evaluated differently by different people. It is mostly defined as the sense by which certain properties are perceived through the stimulation of the taste buds (the gustatory sense) when the food is chewed and comes in contact with the various areas of the tongue. The four basic tastes are salty, sweet, sour and bitter. 
TBA  To Be Advised or To Be Agreed 
TBD  To be declared 
TBMA  To be mutually agreed 
TBN  To Be Named or To Be Narrowed or To Be Nominated 
TBN or TOBENA  To be Named; To be narrowed; To be Nominated 
TBOOK  To the Best Of Owners Knowledge 
TBR  To Be Renamed 
TBR or TBRN or TRND  To Be Renamed 
TBT  Tributyltin, used in tin-based antifouling 
TC  Time charter. Owners agree to hire a particular ship for a set length of time and provide technical management, crewing etc. 
TC  Tank Cleaning or Till Countermanded or Temperature Controlled (container) 
TC-LO  Toxic Concentration Low. This is the lowest concentration of an airborne substance to which humans or animals have been exposed that resulted in any toxic effects in humans or produced any tumors or adverse reproductive effects in animals or humans  
TCE  Time charter equivalent 
TCH  Time charter hire 
TCL  Tank Cleaning 
TCM  Convention on the International Combined Transport of Goods 
TCP  Time Charter Party. The document containing the terms and conditions of a contract between a charterer and a shipowner for the hire of a ship for a fixed time frame, usually more than one voyage. 
TCT  Time charter Trip 
TCV  Total Calcuated Volume 
TCY  Time charter yield 
TD-LO  Toxic Dose Low. The lowest dose of a hazardous substance introduced by means other than inhalation over a given time period that has been reported to produce toxic effects in humans or produced any tumors or adverse reproductive effects in animals or humans.  
TDI  Tolune Diisocyanate. TDI is an isocyanate used in the production of polyurethanes for flexible foam applications ranging from furniture, bedding, and carpet underlay, to transportation and packaging. TDI is also used in the manufacture of coatings, sealants, adhesives, and elastomers 
TDK or TWD  Tween Decker 
TDW  Tons deadweight 
TEA  Triethanolamine. See ethanolamine 
TECH  Toxic, explosive, corrosive and hazardous (dangerous cargo) 
Technical Management  Service where a hired agent operates a ship and receives a fee in return. 
Technical Operator  "Technical Operator means an entity dealing with the responsibility for operation of the ship and which, on assuming such responsibility, has agreed to take over all the duties and responsibilities imposed by the ISM code and, where applicable, holds the Document of Compliance." 
TELCON  Telephone Conversation 
Telex  Used for sending messages to outside companies. Messages are transmitted via Western Union, ITT and RCA.Being replaced by fax and internet. 
Temperature Recorder  A device to record temperature in a container while cargo is en route. 
TEN  Trans European Network 
Tender  The offer of goods for transportation or the offer to place cars or containers for loading or unload- ing. 
Tenor  Time and date for payment of a draft. 
TEPA  Tetraethylenepentamine 
Teratogen  Causes physical defects in the developing embryo 
Term Deal  An agreement for a customer, or lifter, to buy a supplier's oil over a period of time. Such arrangements obligate seller to provide and purchaser to take, and pay for, a named quantity of specified merchandise at a defined price over a number of months or years, usually according to some sort of schedule. The opposite of a spot deal. 
Terminal  An area where a ship''s cargo is loaded or unloaded. 
Terminal Buoy  A terminal buoy 
Terminal Charge  A charge made for a service performed in a carrier’s terminal area. 
Terms of Sale  The point at which sellers have fulfilled their obligations so the goods in a legal sense could be said to have been delivered to the buyer. They are shorthand expressions that set out the rights and obliga- tions of each party when it comes to transporting the goods. Following, are the thirteen terms of sale in international trade as Terms of Sale reflected in the recent amendment to the International chamber of Commerce Terms of Trade (INCOTERMS), effective July 1990: exw, fca, fas, fob, cfr, cif, cpt, cip, daf, des, deq, ddu and ddp. 
Testicular toxicity  Causing injury to the testis; a specific subdivision of reproductive toxicity. 
TEU  Twenty feet Equivalent Unit (or a container). A dry cargo container unit measuring 40 X 8 X 8.5 feet used as a measure of container capacity. 
TF  Therefore 
TFA  Trans Fatty Acids. TFA is naturally present in animal fats and are formed during the partial hydrogenation of oils. They are unsaturated fatty acids in which the hydrogen atoms attached to the carbon atoms in the double bond are on opposite sides of the double bond, whereas these hydrogen atoms are on the same side of the double bond in ""cis"" unsaturated fatty acids. The trans fatty acids have a relatively straight hydrocarbon chain, whereas ""cis"" fatty acids are bent at the point of the double bond. The difference in structures allows closer packing of molecules of trans fatty acids and triglyceride molecules which contain them. Consequently, the trans fatty acids and their triglycerides have higher melting points than the corresponding ""cis"" fatty acids and their triglycerides. 
TFDE Propulsion  Tri-Fuel Diesel Electric Propulsion - The name TFDE originates mainly due to the power generation engines being able to use three different types of fuel, thus the name "tri-fuel diesel electric propulsion." These are specifically used in LNG carriers. 
TFW  Tropical fresh water loadline 
TG  Tug 
THC  Terminal Handling Charges 
The Bitter End  The end of an anchor cable is fastened to the bitts at the ship's bow. If all of the anchor cable has been payed out you have come to the bitter end. 
The Devil to Pay  To pay the deck seams meant to seal them with tar. The devil seam was the most difficult to pay because it was curved and intersected with the straight deck planking. Some sources define the "devil" as the below-the-waterline-seam between the keel and the the adjoining planking. Paying the Devil was considered to be a most difficult and unpleasant task. 
Theatre Vessel  A mobile vessel used as a theatre 
Thermal Cracker  Originally, the name of the refining industry's first molecule breaker. These units used heat and pressure to turn heavy fuel oil into gasoline and distillate. Today, the term applies to a category of bottoms crackers, including visbreakers and cokers, which rely on heat to destroy residue. 
Thermal cracking  Thermal cracking is a petroleum refining process used to break up heavy oil molecules into lighter, more valuable fractions (e.g. gasoline, kerosene) by the use of high temperature without the aid of catalysts. It is used to convert gas oils into naphtha. 
Thermal Stability  Reluctance to change, especially to deteriorate, when heated. A property particularly associated with aviation turbine fuels. 
Thermoforming  The process of heating a thermoplastic sheet to a working temperature and then forming it into a finished shape by means of heat or pressure. (Modern Plastics Encyclopedia 1995) 
Thermoplastic  A plastic which is solid when cold, but which may flow and be re-formed multiple times with the application of heat. Some plastics are dissolved in solvents such as water (a latex) to aid their application. 
Thermoset  A polymer that solidifies when heated, in other words it sets and cannot thereafter be changed, is called a thermoset. Some polymers behave like this because the heating process causes the chains of the polymer to bind to each other, via cross-links, and these cannot then be broken. Polymers that remain malleable after heating and cooling are referred to as thermoplastics. Polymers of this kind can also be cross-linked by the addition of certain cross-linking agents and turned into rigid materials. 
Third Party Logistics (3PL)  A company that provides logistics services to other companies for some or all of their logistics needs. It typically includes warehousing and transportation services. Most 3PL’s also have freight forwarding licenses. 
Third-Party Processing  see TOLL PROCESSING 
THP  Thrust horse-power 
THR  THRuster 
Three Sheets to the Wind  A sheet is a rope line which controls the tension on the downwind side of a square sail. If, on a three masted fully rigged ship, the sheets of the three lower course sails are loose, the sails will flap and flutter and are said to be "in the wind". A ship in this condition would stagger and wander aimlessly downwind. 
Through Rate  The total rate from the point of origin to final destination. 
Throughput Charge  The charge for moving a container through a container yard off or onto a ship. 
Thwartships  At right angles to the centre-line of the ship  
TIB  Trimmed in bunkers 
Tide  The periodic rise and fall of water level in the oceans 
Tide Over  At first glance, this would seem to be an obviously nautical term. Today it means to make a small bit of something, usually money, last until a supply comes in, as in borrowing some money to tide you over till payday. However, the meaning has changed over the years. Once upon a time, ships could move under sail power, or in the absence of wind, float along with the tide, called a tide over. One could say the floating would tide the ship over until wind came again to move it along. 
Time Bar  The expiration of the time period within which a lawsuit can be brought or arbitration commenced against a carrier for any claim under a contract of carriage. This time period is usually stipulated in the contract of carriage and can be extended or abridged by agreement of the two parties. 
Time Charter  see "Charter, Time". 
Time chartered vessels  "Time chartered vessels means vessels contracted for a period of 6 months or more." 
Time Draft  A draft that matures either a certain number of days after acceptance or a certain number of days after the date of the draft. 
Time lost waiting for berth to count as loading or discharging time or as laytime  TIME LOST WAITING FOR BERTH TO COUNT AS LOADING OR DISCHARGING TIME or AS LAYTIME shall mean that if no loading or discharging Berth is available and the Vessel is unable to tender Notice of Readiness at the waiting-place then any time lost to the Vessel is counted as if Laytime were running, or as time on Demurrage if Laytime has expired. Such time ceases to count once the Berth becomes available. When the Vessel reaches a place where she is able to tender Notice of Readiness, Laytime or time on Demurrage resumes after such tender and, in respect of Laytime, on expiry of any notice time provided in the CharterParty. 
Time Swap  An exchange which involves today's barrels for tomorrow's or next week's for next month's. 
Time-Charter  Lease of a ship to a charterer for a period of time rather than for the performance of a specific voyage. An elemental version of this arrangement, called a bare boat charter, works like renting an unfurnished apartment. The charterer must provide his own master and crew. In other cases the owner provides personnel and various services. 
TIP  Taking inward pilot 
TIR  Transport International par la Route. Road transport operating agreement among European governments and the United States for the international movement of cargo by road. Display of the TIR carnet allows sealed containerloads to cross national frontiers without inspection. 
Titration   The strength of a chemical solution is often determined by reacting the chemical with another in measured amounts. Knowing the chemical reaction involved and the amount of the second reactant, the amount of the first reactant can be calculated. The process of reacting and matching the two solutions is called titration. One example is the determination of free fatty acid content by titration with an alkali. 
Titre Test  The titre is the highest temperature reached during the crystallisation of fatty acids under controlled cooling conditions. It is an important characteristic of inedible fats used for soap making or as a raw material for acid manufacture and it is also an indication of the firmness of natural fats. 
TIW  Total insured value 
TL  Turkish LLoyd 
TLO  Total loss only 
TLV  Threshold Limit Value 
TLX  Telex 
TMK  Tonnage mark 
TMSA  Tanker Management Self Assessment: The Tanker Management and Self Assessment (TMSA) programme provides ship operators with a means to improve and measure their own management systems. The programme encourages ship operators to assess their safety managem 
TNC  Time to next cargo 
TNGE  Tonnage 
TNS / TS  Tons 
To Average Laytime  TO AVERAGE LAYTIME shall mean that separate calculations are to be made for loading and discharging and that any time saved in one operation is to be set off against any excess time used in the other. 
To Know the Ropes  There was miles and miles of cordage in the rigging of a square rigged ship. The only way of keeping track of and knowing the function of all of these lines was to know where they were located. It took an experienced seaman to know the ropes. 
Tocopherol  A natural antioxidant found in vegetable oils and fats. There are four naturally occurring tocopherol homologs, i.e. a-, ß-, y- and d- tocopherols. In addition, there are four analogous tocotrienols with the same chemical structures, but having three double bonds in the side chain. Palm oil contains both a tocopherol and tocotrienols. Tocopherols are also known as Vitamin E - the most active is a- tocopherol. 
Toe the Line  When called to line up at attention, the ship's crew would form up with their toes touching a seam in the deck planking. 
TOFA  Tall Oil Fatty Acids. An important industrial feedstock that is a by-product of the wood pulp industry. The term ""tall oil"" is derived from the Swedish word for ""pine oil"", or tallolja. Production occurs mainly in North America and Scandinavia. TOFA are obtained from crude tall oil via fractional distillation and yield between 25- 35% fatty acids (oleic and linoleic). 
TOFC  Trailer on Flat Car: The movement of a highway trailer on a railroad flatcar. Also known as Piggyback. 
Toll Processing  Refining or petrochemicals production done on a fee basis. A plant owner puts another party's feedstock through his equipment and charges for the service. A portion of the product retained by the processor may constitute payment. This form of compensation occurs frequently in refining because the feedstock supplier often wants only one part of the output slate. 
Toluene  Gasoline blenders and petrochemicals makers continually compete for possession of this aromatic. Its high octane and low vapor pressure make it an excellent blendstock. The chance to turn it into benzene appeals to the chemical industry. Refineries and steam crackers both produce it in large quantities. 
Toluene  Toluene, a colorless liquid, is an aromatic hydrocarbon used extensively as starting material for the manufacture of industrial chemicals. Its major end-products are polyurethanes. 
TOM  Tomorrow 
TOMK  To make 
TON  Ton of 1000 Kilos. a unit of measurement used in shipping assuming 100 cubic feet of cargo equals one ton, equals 2000 pounds and is also called a “short ton”, a “long ton” equals 2240 pounds, and a “tonne” is 2204 pounds 
TON  Turn over or Transfer order 
Ton Mile  Equivalent to transporting one ton of cargo over a distance of one mile. 
Ton–Mile  – A unit used in comparing freight earnings or expenses. The amount earned from the cost of hauling a ton of freight one mile.
– The movement of a ton of freight one mile. 
Tonnage  Cubic capacity of a ship. 
Tonne  Metric ton equivalent to 1,000 kilograms or 2204 pounds 
Tons Per Inch  Ship Stability: TPI=Area of WP/420 
TOP  Taking Outward Pilot 
Top–Air Delivery  A type of air circulation in a container. In top air units, air is drawn from the bottom of the container, filtered through the evaporator for cooling and then forced through the ducted passages along the top of the container. This type of airflow requires a special loading pattern. 
Topping Plant  A simple refinery, one which lacks cracking and other upgrading equipment. The name comes from what such basic installations can do. They boil the straight-run light products, the top, off crude oil. The most rudimentary topping plants have no complex hardware at all. A slightly more sophisticated type adds a vacuum still to separate VGO from the crude unit's residue, but the facility would not have a cracker to convert the VGO. 
Topping Yields  The product slate obtained by processing a grade of crude in a simple refinery. In everyday industry usage, the term usually means the yield from atmospheric distillation followed by naphtha reforming and finished product blending. 
Topside  The sides of a ship between the waterline and the deck; sometimes referring to onto or above the deck  
TOR  Time on risk 
Torpedo Boat  A combat vessel designed for launching torpedoes, usually small and fast  
Torpedo Recovery Vessel  A naval auxiliary vessel designed for recovering unexploded or training torpedoes 
Torpedo Trials Vessel  A naval auxiliary vessel for testing and conducting trails on torpedoes 
TOTCOM  Total commission 
Totox Value  Index of the degree of oxidation in which the peroxide value and anisidine value are combined - Totox = 2PV + AV 
Touch and Go  This referred to a ship's keel touching the bottom and getting right off again. 
TOVALOP  Tanker Owners Voluntary Agreement to Limit Oil Pollution 
Towage  Act of towing a ship. 
Towboat  A towboat is a powerful boat with a flat front that pushes barges on rivers. Towboats typically have flat hulls to accommodate the shallower depths of the nation's inland waterways. 
Towing/Pushing, Inland Waterways  A vessel designed for tug, towing or pushing operations. Not designed for operation in open sea 
Towline  Towlines or hawsers are constructed of extremely strong synthetic materials or steel wire. When the towline connection with the barge forms a "Y" shape to reduce chafing, it is known as abridle. 
Toxic  Poison which can affect personnel through inhalation, absorption or ingestion. For the purposes of this policy the term toxic is taken to include all products which give off vapours containing substances for which exposure limits are recommended as they  
TP  Time in Port 
TP  Time in Port 
TP R/V or TPRV  Trans Pacific Round Voyage 
TPC  Tons Per Centimetre 
TPC Immersion  the amount of tons that it takes to lower a ship's draft one centimeter 
TPCM  Tons per cubic meter 
TPD  Tons per day 
TPI  Tons per inch. Measure of vessel capacity equal to the weight of displaced water if vessel draft were to change by one inch.  
TPRG  Terminal Policy Review Group 
TPSG  Terminal Policy Steering Group 
TQ  As found, or Just as it is 
TR  Tons Registered 
Trace Metals  Refers to metals which are present in very small amounts. Copper and iron are trace metals found in vegetable oils. The level decreases in refining and increases if there is contamination. 
Tractor  Unit of highway motive power used to pull one or more trailers/containers. 
Trade Acceptance  A time or a date draft that has been accepted by the buyer (the drawee) for payment at maturity. 
Trading Limits  Geographical limits specified in a time charter party outside which the charterer is not allowed to operate the ship. 
Traffic  Persons and property carried by transport lines. 
Traffic Diversion  Any commodity flow which ceases to use the project under some project alternative or scenario. 
Trailer  The truck unit into which freight is loaded as in tractor trailer combination. See Container. 
Training Ship  A vessel equipped for training seafarers 
Training Ship, Naval Auxiliary  A vessel used for training merchant or naval seamen. 
Tramp Line  An ocean carrier company operating vessels not on regular runs or schedules.They call at any port where cargo may be available. 
Tramp Shipping  The employment of ships in trades where there are no published schedules, in contrast to liner shipping. 
Trans  A geometric isomer of an unsaturated fatty acid where hydrocarbons attached to the carbons comprising the double bond are on opposite sides of the carbon chain. 
Trans Shipment Barge, non propelled  A non propelled pontoon used for the storage and or trans shipment of cargoes 
Trans Shipment Vessel  A vessel equipped for the trans shipment of dry cargo to other vessels alongside. May also be able to store cargo until trans shipment. 
Transaction Currency  The currency used on a single invoice/voucher 
Transhipment  Applies to lightening operations and "ship to ship" (STS) transfers both at anchor and underway, or where vessels are "double banked" alongside a berth. 
Transpassive state  State of the metal polarized to a potential value above the range of a passive state, characterized by a considerable increase of the corrosion currents but no pitting corrosion 
Transport  To move cargo from one place to another. 
Transportation & Exit (T&E)  Allows foreign merchandise arriving at one port to be transported in bond through the U.S. to be exported from another port, without paying duty. 
Transportation Worker Identification Credential (TWIC)  Established by Congress through the Maritime Transportation Security Act (MTSA) and is adminis- tered by the Transportation Security Administration (TSA) and U.S. Coast Guard. TWICs are tamper– resistant biometric credentials that will be issued to all credentialed merchant mariners and to workers who require unescorted access to secure areas of ports, vessels or outer continental shelf facilities. 
Transship  To transfer goods from one transportation line to another, or from one ship to another. 
Transshipment Port  Place where cargo is transferred to another carrier. 
Transverse Axis  Ship Stability: The lateral axis passes through the ship from side to side. Rotation about this axis is called pitch. Pitch changes the vertical direction the aircraft's nose is pointing. The elevators are the primary control of pitch. 
Trawler  A vessel for catching fish by trawling with nets handled over the side 
Trenching Support Vessel  A vessel primarily equipped to operate submersibles for digging trenches on the sea bed for pipes and cables 
Trf  Tariff: A publication setting forth the charges, rates and rules of transportation companies. 
Triglycerides  See Glyceride 
Trim  The difference between the fore and aft draught of the vessel. When the aft draught is greater that the forward draught, the vessel is said to be trimmed 'by the stern'. When the aft draught is greater than the forward draught, the vessel is said to be trimmed 'by the head'. 
Trim  The angle at which a ship floats when viewed from the side. It can rest stern high, bow high, or on an even keel. Masters must load their ships with safe trim in mind. 
Troopship  A naval auxiliary vessel. Designed for carrying troops 
True Colors  The current meaning, ‘to reveal yourself as you really are’, actually came about because of the opposite phrase “false colors” – from the 17th century referring to a vessel which sailed under a flag not her own. This tactic was used by almost everyone as a ruse de guerre, but the rules of gentlemanly behavior (and possibly actual legal rules) required one to raise one’s true colors before opening fire on another ship. 
True Draft  Ship Stability: Where the waterline intersects the forward and after perpendiculars. 
Trust Receipt  Release of merchandise by a bank to a buyer while the bank retains title to the merchandise. The goods are usually obtained for manufacturing or sales purposes. The buyer is obligated to maintain the goods (or the proceeds from their sales) distinct from the remainder of the assets and to hold them ready for repossession by the bank. 
Try a Different Tack  The direction in which a ship moves as determined by the position of its sails and regarded in terms of the direction of the wind (starboard tack). If one tack didn’t bring the ship up properly, one could always attempt another. 
TS  Time at Sea or Tons 
TSG (C)(G)  Tanker Safety Guide (Chemicals) and (Gas) (ICS) 
TSP  Triple super phosphate 
TSS  Twin screw ship 
TST  Topside tank 
TT  Turn Time or Telegraphic Transfer or That or TankTop 
TTBE  Turn Time Both Ends 
TTL  Total 
TUB  Tubarao 
Tug  A powerful small boat designed to pull, push or manuever vessels. 
Tug, Naval Auxiliary  A tug for naval support 
Tugboat / Ocean Towing  Tugboats are used to pull ortow barges on the ocean or on wider inland rivers that have rough waters. Ocean towing involves long towlines between the tugboat and tow, to provide the necessary slack to accommodate rough water and varied weather conditions. Oceangoing tugs are very large and very powerful. 
Turn a Blind Eye  From Admiral Lord Nelson’s awesome display of badassery at the Battle of Copenhagen. When the signal was given to stop fighting, Nelson held his spyglass to his blind eye and insisted he didn’t see the signal. He then proceeded to kick butt, of course. 
Turnaround  In water transportation, the time it takes between the arrival of a vessel and its departure. 
Turning Basin  An area that provides for the turning of a ship (bow to stern). Turning basins are usually located at or near the upper end of the interior channel and possibly at one or more intermediate points along long channels (EM 1110-2-1613). 
Turret  An attachment for a Floating Storage and Offtake vessel or Floating Production, Storage and Offloading vessel that allows vessel to rotate around its mooring according to direction of wind and current. 
TV  Time volume 
TVE  Tank Vessel Examination (USCG) 
TVP  True Vapor Pressure. The absolute pressure exerted by the gas produced by evaporation from a liquid, when the gas and liquid are in equilibrium at the prevailing temperature. 
TW  Tween Deck (OCIMF acronym) 
TW  Twin Decker 
TWA  Time Weighted Average. Time-weighted average concentration for an 8-hour workday and a 40-hour-work week in which a worker may be repeatedly exposed without adverse health effects 
TWD  Tween Decker 
TWHD  Tons per working or Workable hatch per day 
Twist Locks  A set of four twistable bayonet type shear keys used as part of a spreader to pick up a container or as part of a chassis to secure the containers. 
Two–Way Pallet  A pallet so designed that the forks of a fork lift truck can be inserted from two sides only. 
TX  Tank (OCIMF acronym) 
TX  Telex or Transmitter (Radio) 
Typicals  specifications considered representative of a crude or product stream. Parcels, particularly of feedstocks, often trade on typicals even though such data carries no absolute commitments or legal obligations. 
TYT  Thanks your telex