Rope Glossary


A species of banana plant grown almost exclusively in the Philippines; the fiber of which is processed to become Manila rope. The abaca is also grown in Central America, Sumatara and Borneo.

Abrasion Resistance:

The ability of a fiber or rope to withstand surface wear and rubbing due to motion against other fibers or rope components (internal abrasion) or a contact surface such as wraps on a winch drum (external abrasion), which can be a portion of the rope itself.

Acceleration Stress:

Additional stress placed on rope due to increasing the velocity of load.

After Spring Line:

Leads aft from the ship and keeps the ship from moving forward.

Alaskan King Crab Line:

A specialty rope of various materials used in King Crab fishing. Characterized by its firmness of lay.

Anchor Line:

Rope with a thimble spliced into one end for attaching an anchor.

Awning Cord:

Small diameter cord used for many utility purposes; most commonly a cotton braid with stretch resistant fiber core.

Back Splice:

A method to finish off the end of a rope by burying the end back into the center for braids or splicing the strands back into the body of a twisted rope.


A stay to keep a mast from leaning forward. Can either be fixed or running. Running backstays are rigged on both sides of the boat and are set up or slacked off depending on the point of sailing.

Baler Twine:

Single ply twine, usually of sisal or polypropylene, used by farmers for tying bales of hay.


A knot used to join two ends or two separate ropes together.


A loop made in any part of a rope, line or chain.

Binder Twine:

A twine used in binding and for other utility purposes; most commonly of natural fibers – jute, sisal, etc…


A post or pair of posts with or without a crossbar (norman) for securing heavy lines; usually in the bow of a boat.

Bitter End:

in tying knots or splicing, refers to the end opposite the end in use. Used to give mechanical advantage when lifting or pulling heavy weights.


A combination of rope mix of different synthetic fibers to form one rope.


A pulley; there are many kinds – single, double, snatch, cheek, etc… The rope runs over the sheave set between the two shells (cheeks) of the block. Also a die of steel in the form of a tube of a desired diameter into which yarns are fed to be formed into a strand of rope.

Block Creel:

A method of rope making where a given length of rope is produced from a rope making machine where all the subcomponents of the rope structure are continuous without splices. The term arises from filling all creels or bobbins to maximum (block creels) and ending rope making when the first one empties.

Blown Filament:

Monofilament polypropylene into which is blown a special gas during extrusion. This produces a lighter, less expensive and less strong rope, size for size, than standard polypropylene; also called foamed filament.


A round heavy post for securing lines; sometimes on a boat but usually on a pier.


A liquid coating that increases abrasion resistance and prevents water absorption.

Bow Head Line:

Runs through the bullnose and controls aft movement and assists the breast lines. Forward Spring.


n. A rope or textile structure formed by a braiding process. v. The intertwining of strands in a braiding process to produce a tubular rope structure.

Braid, Double:

A rope constructed from an inner hollow braided rope (core) which has another hollow braided rope constructed around its exterior (cover). Core and cover may be either plain or twill braid and both share any load on the rope, but not necessarily in equal amounts. Also called “braid-on-braid.”

Braid, Hollow

(Also: Braid,Single; Braid, Diamond): A single braid rope construction of either plain or twill braid. The center is hollow. On the surface all strands are parallel to the axis.

Braid, Solid:

A cylindrical braid in which each strand alternately passes under and over one or more of the other strands of the rope while all strands are rotating around the axis with the same direction of rotation. On the surface, all strands appear to be parallel to the axis.

Braider Splice:

In a braided rope, the continuation of a single interrupted strand (or multiple strands) with another identical strand, which is braided from the same carrier. The interrupted and replacement strands are arranged in parallel over some distance, and are buried, or tucked, into the braid so as to secure them into the braid. To maintain maximum strength, the strands should overlap one another for a sufficient distance.


A period of use in which the filaments of a rope settle in together; thus the rope lengthens somewhat.

Breaking Length:

A convenient term for comparing the strength-to-weight ratio of textile structures from one product to another. The calculated length of a specimen whose weight is equal to the breaking load.

Breaking Strength:

For cordage, the nominal force (or load) that would be expected to break or rupture a single specimen in a tensile test conducted under a specified procedure. On a group of like specimens it may be expressed as an average or as a minimum based on statistical analysis.

Note: Breaking force refers to an external force applied to an individual specimen to produce rupture, whereas breaking strength preferably should be restricted to the characteristic average force required to rupture several specimens of a sample. While the breaking strength is numerically equal to the breaking force for an individual specimen, the average breaking force observed for two or more specimens of a specific sample is referred to or used as the breaking strength of the sample.

Breaking Strength, Minimum:

Cordage Institute standard. A value based on a statistically significant number of breaking load tests and the standard deviation used to establish the minimum value.

Breast Line:

A line that leads to a right angle to the centerline of the ship and controls the distance from the pier.

Cable Laid Rope:

Consists of three small ropes twisted together to form a single rope.


A rotating cylinder used in winding a rope or cable; also used in spinning and twisting yarn, twine or rope.


Part of a cordage braiding machine that carries the group of yarns or the single yarn like a single strand through the braid as it is made. May also refer to that yarn or group of yarns.


A heavy line used for general hoisting in oil well drilling; also called cathead line.

Chafing Gear:

any device:

leather, rope, plastic, etc… used to prevent lines, sails, decks or spars from wear.

Chalk and Mason Line:

Small cords of various fibers, braided or twisted, used in construction for marking straight lines, the cord must have a rough texture to hold chalk.

Class I Rope:

Rope constructions produced with non high modulus fibers that impart the strength and stretch characteristics to the rope which have tenacities of 15 grams/denier (gpd) or less and a total stretch at break of 6% or greater. Typical Class I ropes are produced with traditional fibers such as: olefin (polypropylene or polyethylene), nylon, and polyester. These fibers can be used in combination or singularly in the various rope constructions such as: 3-strand, 8-strand, 12-strand braids, double braids, or core dependent braids.

Class II Rope:

Rope constructions produced with high modulus fibers that impart the strength and stretch characteristics to the rope which have tenacities greater than 15 grams/denier (gpd) and a total stretch at break of less than 6%. Typical Class II ropes are produced with: HMPE (Dyneema® fiber or Spectra®), Aramid (Technora® or Kevlar®), LCP (Vectran®), PBO (ZYLON®), and Carbon fibers. These fibers can be used in combination or singularly in the various ropes constructions such as: 3-strand, 8-strand, 12-strand, double braids, or core-dependent braids.

Co-efficient of Friction:

Gripping ability important for rope use on winches and in situations where slipperiness can be dangerous or cause problems. Gripping depends upon the friction or texture of the rope itself, its elasticity, creep (or taffy effect, as in monofilament polypropylene), the area of contact and the ratio of rope size to bitt size.


A naturally occurring or synthetic compound consisting of large molecules made up of a linked series of two or more different repeated simple monomers.

Combo or Combination:

Blend of two or more rope materials into one cord.

Composite Rope:

A combination of polypropylene/polyester or other combinations of fiber types.


String, line, rope, twisted or braided, generally refers to small sizes one inch diameter and under.

Core-Dependent Braids:

Cover braided rope constructions that utilize an internal core member or members to create the strength and stretch characteristics of the rope. The primary function of the external cover braid is to contain the core or cores and create the degree of rope firmness desired. Based on the fiber or combination of fibers used in the cover braid, the following characteristics of the rope can be altered: coefficient of friction, wear resistance, specific gravity, and heat resistance due to friction. Core-dependent braided ropes typically have internal strength members produced with parallel bundled fiber cores, a single braid core, multiple braid cores, or multiple 3 strand cores. This type of rope construction can be produced with traditional fibers, high modulus fibers, or combinations of both fiber groups, and offers the potential of creating a wide range of design parameters.

Cork Line:

A floating line, braided or twisted, made of regular or foamed polypropylene. May have nylon or polyester protective covering for greater abrasion resistance; also called float line.

Crab Lay:

An exceptionally tight twist given to rope used in the crab fishing industry. The hard lay is necessary to prevent hockling.

Crab Trap Line:

A small diameter cord used for lifting crab traps. May be twisted or braided. Cotton is the most common though various fibers may be used.


Manila rope spliced to the end of a wire rope drilling line.


The “taffy effect” – a slow flow of synthetic material such as polypropylene under high temperature or great pressure.


To bend, kink, curl or wave a fiber to give it more loft.

Crown Splice:

Braiding or splicing the end of a rope into itself to prevent fraying and unraveling. An alternative to whipping.

Curtain Cord:

Small diameter cord used for drapery, traverse cords, etc. Most commonly made of braided cotton with various fiber cores.

Cycle Length:

The length along the axis required for a strand to make one revolution around the rope.


DuPont trademark for polyester.


The loss of desirable physical properties by a textile material due to some process of physical/chemical phenomenon.


The system used internationally for the numbering of silk and man-made filament yarns, except glass yarns. It is the primary unit for determining the size of a yarn and is based on its linear density. Officially, it is defined as the number unit weights of 0.05 grams per 450-meter length. Denier is equivalent numerically to the number of grams per 9,000 meters. In the English numbering system, 1 denier equals 4,464,528 yards to the pound. Denier is also used to indicate the thickness of a man-made fiber staple. For example, a staple is said to be 3 denier if 1,488,176 linear yards of the staple (were it continuous) would weigh one pound. The metric equivalent is Tex, the grams mass of 10,000 meters of yarn.

Diamond Braid:

Cordage construction with 8, 12 or 16 strands of fibers braided under and over each other in a circular direction. The center of the rope may be hollow, such as in a hollow braid, allowing for easy splicing; or it may have a center rope of parallel fibers. It is generally stronger than solid braid, but not as strong as twisted or braid on braid cordage.


A non-conductor or poor conductor of electricity. Polypropylene has excellent dielectric properties.

Double Braid:

Cordage construction with a jacket braided over a braided rope core; two ropes in one. A very strong and flexible rope that doesn’t hockle, kink or rotate under a load. It is spliceable; also called braid on braid, double spliceable braid and yacht braid.


In sailing, tackle lifted to the boom gooseneck to keep a proper strain on the forward edge of the sail.

Drapery Cord:

Braided cord of small diameter made usually of cotton with various types of fiber core, such as fiberglass, polyester, etc. Used as draw cords, traverse cords and curtain cords.


Partially closing the knot by drawing up the knot to make sure the knot is tied correctly.

Dynamic Load (for cordage):

Any rapidly applied load that increases the load significantly above the normal static load when lifting or suspending a weight. Dynamic effects are greater on a low elongation rope such as manila than on a higher elongation rope such as nylon, and greater on a shorter rope than on a longer one. Also, any rapidly applied load to cordage that may change its properties significantly when compared to slowly applied loads.

Dynamic Loading:

A sudden or rapid force applied to a rope caused by stopping, jerking, swinging, etc. In some cases, the force may be two, three, or even more times the normal load involved. For example, picking up a tow on a slack line or stopping a falling object, can cause a dynamic loading of a rope. Working loads do not apply under such conditions.

Easing Out Line:

A length of line that is secured at one end, with a bight thrown over the hook on a hose and run back to a cleat, allowing the hose to be gently retrieved. Used during high line operations.

Eight Strand:

A plaited (or braided) construction of eight strands; usually found in large sizes for mooring, shipping and towing uses. Exhibits no torque in heavy towing. Made of various fibers.

Elastic Recovery:

The degree that a fiber, yarn, or cord will return to its original size and shape after deformation from stress.


The deformation in the direction of load caused by a tensile force. Elongation is measured in units of length (e.g. millimeters, inches) or calculated as a percentage of the original specimen length. Elongation may be measured at any specified load or at the breaking load.


An end is simply one of the twisted yarns that make up the strand. Use either 1, 2, 3, or more ends to make a strand in a covered braid. There can be more ends in a core braid.


To push a melted resin through small tube shaped dies, thus forming a single fiber, as in monofilament or multifilament polypropylene. Split film polypropylene is extruded into sheets of plastic and split into ribbon-like fibers that are twisted into rope.


For polymer filaments. The process of producing filaments by forcing a polymer through a die.


A temporary or permanent loop in a line.

Eye Splice:

A fixed loop formed in the end of a line by splicing the end back into its standing part.


A unit of measurement. One fathom is approximately six feet.


The tendency of a material to weaken or fail during alternate tension-tension or tension-compression cycles. In cordage, particularly at loads well below the breaking strength, this degradation is often caused by internal abrasion of the fibers and yarns but may also be caused by fiber damage due to compression. Some fibers develop cracks or splits that cause failure, especially at relatively high loads.


A long, fine, very flexible structure that may be woven, braided, or twisted into a variety of fabrics, twine, cordage or rope.


An extruded filament used in making rope. When a single filament is laid out, it resembles a net of loosely bonded fibers.


A tapering pin used to open the strands of a rope prior to splicing. It is sometimes hollow.

Fid Length:

A fid length equals 21 times the diameter of the rope or 7 times the circumference.


A fine or thinly spun thread; a fiber.


An oil, emulsion, lubricant or the like, applied to fibers to prevent damage during textile processing or to improve performance during use of the product.


Method of disposing a line by coiling it tightly flat on deck with the second inside the first, and so on.

Float Line:

A braided or twisted rope made primarily of foamed or regular polypropylene so that it floats; also called cork line or top line.


A monofilament polypropylene into which gas is blown during extrusion. This produces a lighter weight, less expensive, less strong rope size for size than standard polypropylene.


Rope making equipment which combines and twists several yarns into a single strand.

Forward Spring Line:

Leads forward from the ship and keeps the ship from moving aft.

Four Stage Construction:

A manufacturing process for making three strand twisted rope. The four stages are:

Twisting fibers into one ply yarn
Twisting these yarns into three ply yarn
Forming the strand
Twisting three strands together into finished rope.

Friction Hitch:

A knot tied to another rope, or an object so that it can be adjusted (slid), but stays in place (from friction) when the load is on the standing part.

Genoa Jib:

An oversized jib which overlaps the mainsail and is controlled outside the rigging and is used chiefly in races to give a boat more speed.


In sailing, a fitting which holds the boom to the mast. Guy Ropes – Lines used for steadying, guiding or holding something.


A line used to hoist or lower a sail or a flag.


The feel of rope to the touch, its roughness, slipperiness. etc.

Hand Line:

A small diameter rope managed chiefly by direct contact with the hands; used in fishing and in the utilities industries.


A looped bundle of cordage. A means of packaging rope or cords by winding it into a series of loops and tying them about the center.


A heavy line of fiber that is over 5″ in circumference, used in mooring or towing vessels.

Heading Twine:

A small diameter twine usually of braided nylon used by commercial fishermen for tying pot heads.

Heat Resistance:

The ability of fibers and ropes to resist breakdown, loss of strength, at high temperatures. Heat resistance is normally an inherent property of the fiber used in manufacturing ropes.

Heaving Line:

Light cotton cord or sash, weighted line thrown across to a ship or pier when coming alongside to act as a messenger for a mooring line.


The fibers of a tall plant, the cannabis sativa, grown in Asia; also called “marijuana” or “Indian hemp”. It may also refer to a fiber similar to true hemp such as manila.


The Agave Fourcroydes, a plant native of Yucatan, Mexico, the fibers of which are used in making sisal cordage.


A knot that attaches a rope to something, like a spar, a post or another rope.


High Modulus Polyethylene.


A back turn; a twist against the lay that cannot be corrected. Damage that occurs to a rope when a load is suddenly released on the line or when a rope is twisted and the strands form a loop. A line may look like it has knots along its length. This type of damage results in substantial loss of strength which cannot be repaired. It can lessen the tensile strength by as much as 50%. Braided or plaited rope cannot hockle.

Hollow Braid:

An easily spliced cord of a diamond braid construction; most common in nylon or polypropylene – for example, water ski tow rope.


The attack of the water ions on polymeric molecules, which results in polymer chain scission and loss of the fiber’s physical properties.


Having the ability to absorb moisture from the atmosphere. All fibers have this property in varying degrees.

– I –

Inherently Buoyant (KAPOK) Lifejacket:

Used by personnel working topside during hazardous conditions or evolutions to ensure flotation in the event the wearer falls overboard. UNREP and boat crews wear them at all times. Sometimes called the Mae West.

– J –


A rope making machine that twists several single ply yarn or single fibers into one larger yarn.


Triangular sail set in forepart of vessel.


A natural fiber obtained from either two Asian plants, Corchorus Capsulans of Corchorus Olitorius; used in sacking and cordage.


A specially designed rope for use in mountain climbing, rescue, repelling, and certain safety applications. It is a generic term of German derivation where mantle refers to the cover and kern the core. These rope are designed for specific uses and should be used only after proper training.


A sharp bend or twist in a rope that permanently distorts the strands.

– L –

Laid Ropes:

Ropes made by twisting of three or more strands together with the twist direction opposite that of the strands.

Laid Up:



A specially constructed rope with a running noose for catching livestock; a lasso. Also a rope used for picketing grazing horses or mules.


To piece together strands to be twisted into rope.

Lay Length:

The actual distance required to make one complete revolution around the axis in any element in a strand, cord or rope.

Lead Line:

Sinking line used in fishing for lower line holding down nets or traps. May have a lead filament or core that would make the rope sink; also called bottom line.

Leaving Line:

A barge mooring line used primarily to tie up unattended barges. A random mix rope is generally used for this purpose.

Left-Handed Twist:

An “s” twist or a twist that would be laid out in a counterclockwise direction.

Life Line:

An anchored line used as a support to someone who may fall or drown; a line shot to a ship in distress either to connect it with the shore or for hauling aboard other life-saving devices; lines rigged to keep the crew aboard in bad weather.

Life Ring:

When an individual is sighted in the water, a ring should be thrown as close to them as possible to provide flotation and make them easier to sight.


The line rigged from the mast which holds the outboard end of the bosom or spinnaker pole in a desired horizontal position.


A piece of rope, either fiber or wire, which is in use or has been cut for a specific purpose, such as lifeline, heaving line or lead line.

Linear Density:

In rope specifications, means weight per given unit of length; for example pounds per 100 feet.

Liquid Crystal Polymer (LCP):

A thermoplastic multifilament yarn spun from a proprietary liquid crystal polymer. LCP fiber is five times stronger than steel and ten times stronger than aluminum for its weight. It has no creep and excellent chemical resistance.

Lock Lines:

A line led from the bow and stern of a tow to the lock wall.


A cordage material is lofted if it is made to yield more feet and diameter per pound by crimping the fibers and/or loosening the twist or weave to give more bulk per unit of weight.

Long Splice:

A method for joining end to end a three stranded rope without increasing the diameter of the rope. Not as strong as a short splice, but essential in splicing rope that must be used in a pulley where rope diameter cannot be changed.


Also called a turn; a circle of rope in which the rope crosses over itself, i.e. the end is placed over the standing part.


The forward edge of a fore-and-aft sail.


A rope by which the mainsail is trimmed and secured.


A cord used for winding around the ends of ropes to prevent fraying.


A pointed spike used to separate strands of rope in splicing.

Mason Line:

A utility cord used for alignment in construction and other uses.


A fiber of the abaca plant used in making rope; also called manila hemp.

Maypole Braid:

A non-spliceable braid constructed with 8, 12, or 16 strands of fibers braided around a center core of parallel fibers. The strands from a herringbone pattern on the

rope. May also refer to diamond braid.


Multi Filament Polypropylene.

MK-1 Lifejacket:

Primarily designed for carrier flight deck personnel. It is also used by other topside working personnel when required.


The ratio of change in stress to change in strain following the removal of crimp from the material being tested; i.e., the ratio of the stress expressed in either force per unit linear density or force per unit area of the original specimen, and the strain expressed as either a fraction of the original length or percentage elongation.

Monkey Fist:

Weighted knot in the end of a heaving line. Usually made up of 2 or 3 ounces of lead wrapped up in a rag.


A yarn consisting of one or more heavy, coarse, continuous filaments produced by the extrusion of a polymeric material suitable for fiber production.

Mooring Line:

A rope or cable used to secure or make fast vessel or aircraft.


A yarn consisting of many fine continuous filaments produced by the spinning of a polymeric material suitable for fiber production.


A process that raises the surface fibers of a fabric, cord or rope by means of rapid passage over metal surfaces.

Natural Fiber:

Any organic fiber such as cotton, jute, manila, sisal, etc.

Nominal Size:

A designation that has been determined by the measurement of another property. For rope, diameter is considered a nominal property and is based upon the measurement of the linear density of the rope in accordance with some standard.


A loop that closes under strain.

Nylon (PA) Fiber:

A manufactured fiber in which the fiber-forming substance (polyamide) is characterized by recurring amide groups as an integral part of the polymer chain. The two principal types of nylon fiber used in rope production are type 6.6 and type 6. The number in the type designation is indicative of the number of carbon atoms separating the acid and amine groups in the polymer chain.


Any of a class unsaturated hydrocarbons such as ethylene’s having the general formula cuH2n. Polypropylene and polyethylene are both made of olefin fibers.


A tackle or small wire reel winch used to pull the lower rear corner of a sail aft along a boom.

– O –

Pay Out:

To let go or slack off a line; it infers that the rate is controlled.


Value indicating the acidity or alkalinity of a material. A pH of 7.0 is neutral; less than 7.0 is acidic, and more than 7.0 is basic.


A pik is the exposed area of a strand traveling in a straight line along the axis of the rope. In a cover braid there are normally 16, 20, 24, or 32 strands. Strands that revolve to the right are usually referred to as “Z” strands. Strands that revolve to the left are “S” strands. Some splicing instructions might also refer to “standard pairs” since braided ropes are constructed with “S” and “Z” strands for a balanced, torque-free construction.


Braided; generally refers to 8-strand large diameter rope in either a square or round braided construction.


One of the strands twisted together to make yarn, rope or thread or twine. Used in combination to indicate a specific number of strands (example 2-ply).

Polished (glazed):

A cotton cord that has been run through a gum and pigment polish to give it a gloss.

Polyester (PET) Fiber:

A manufactured fiber in which the fiber-forming substance (polyester) is characterized by a long chain polymer having 85% by weight of an ester of a substituted aromatic carboxylic acid.
Rope inc. 3 Strand Polyester Rope Page

Polyethylene (PE):

A polyolefin resin, produced from the polymerization of ethylene gas, and used in the production of manufactured fiber. Polyethylene is similar to polypropylene in its properties but has a higher specific gravity and a lower melting point.

Polyethylene, Extended Chain:

A polyolefin fiber that is characterized by the gel spinning of a very high and narrow molecular weight distribution fiber to produce extremely high tenacity material. The strength of the fiber is approximately 10 times that of steel on a weight-for-weight basis.


A long chain molecule from which man-made fibers are derived; produced by linking together molecular units called monomers.

Polypropylene (PP):

A polyolefin resin, produced from the polymerization of propylene gas, and used in the production of manufactured fiber. Polypropylene may be extruded into a number of fiber forms for use by the rope maker.


A monofilament polypropylene into which gas is blown during extrusion; thus, producing a lighter weight, less expensive, less strong rope or twine, size for size, than standard polypropylene. See blown filament and foamed.


A synthetic fiber group in which the fiber forming sustenance is any long-chain synthetic polymer composed of at least 85% by weight of ethylene, propylene, or other olefin units. Polypropylene and polyethylene represent this group.


Short for polypropylene.


A light weight, strong rope with many uses. It is waterproof, resistant to rot, and floats. For most rope requirements, it is the most economical rope to buy.

Pool Rope:

A floating three strand twisted rope made of polypropylene, used as boundary rope in swimming pools; usually identified by one dark blue and two white strands.

Pot Warp:

Specially constructed 3-strand twisted black polypropylene rope used primarily for lobster fishing, but may be used as crab line, net line and for various other purposes.

Black color resists sunlight deterioration.


A device consisting of a sheave mounted in a block or wall, which is used to achieve mechanical advantage when lifting or pulling heavy objects.

Random Mix:

Economy grade rope made from a mixture of synthetic yarns polypropylene, polyester, and nylon. It is also called random polypro, since polypropylene usually forms the bulk of the fiber.

Rattail Stopper:

A braided tapered line used on mooring lines to eliminate losing slack when doubling or singling up. Its purpose is to hold tension while tying off to bits. The rattail is usually secured to an eye on the deck near the bitts. The tension goes from the Capstan to Rattail to Bitts.


A smooth round strand made of several yarns just prior to being twisted or plaited into 3, 4 or 8 strand rope.

Riding Lines:

Four inch manila lines about 45 to 60 feet in length used for hogging to prevent double heads from popping out due to weight.

Right-Hand Twist:

A “Z” twist or a twist that would be laid out in a clockwise direction.

Ring Buoy:

When an individual is sighted in the water, a ring should be thrown as close to them as possible to provide flotation and make them easier to sight.

Rope, Eight-Strand Plaited:

A rope of which the strands are generally plaited in pairs, and mainly used for marine purposes.

Rope, Fiber:

A compact but flexible torsionally balanced structure produced from strands that are laid, plaited or braided together to produce a product that serves to transmit a tensile force between two points. Generally greater than 3/16″ diameter.

Running Rigging:

All lines and gear used to trim and set sails.


A left-handed twist; a twist that would be laid out by turning the yarn or rope in a counterclockwise direction.

Safety Factor:

A number that the tensile strength is divided by in order to determine the safe working load (for new rope in good condition with proper splices).

Sash Cord:

A cord used within the frame of certain windows that works on a pulley to help raise and lower the window easily within its frame. It is generally a solid braid cotton with various fiber cores for low stretch; a sash cord may also be used for other utility purposes.

Sea Anchor:

Cone shaped, made of canvas, open at one end or both ends. Equipped with a tow-line at the large end and a tripping line at the other. Designed to keep the bow of the life raft heading into the seas.

Seine Twine:

A small diameter twine either braided or twisted most commonly of nylon; used in making fish nets, net repairs, fishing line, chalk line, duck decoy, anchor lines and many other utility uses.


To lash or bind ropes together.


To close or tighten a knot.


A small U-shaped fitting often used to join the thimble in an eye splice to the fitting. The open end is connected by a screw pin. (A snap shackle has a spring loaded pin.)


A grooved wheel or roller in a block or pulley over which the rope passes.

Short Splice:

Method for joining rope, end to end, when maximum strength is desired when an increase in diameter is acceptable and/or when only a small amount of rope can be spared for making a splice.

Shock Cord:

An elastic cord used for tie down purposes, snubbing gear, etc. Made of elastic rubber core with a braided synthetic fiber jacket.

S.I.M.A. Extrusion Technology:

The most advanced technological solution in the field of fibrillated and non-fibrillated PP and HDPE tapes production, designed for the fabrication of twisted rope, fishing nets, insulated cables, baler twine, binder twine and other industrial applications.


The fiber of the Agave Sisalana used for making cordage and rope. May also refer to the Henequin or Agave Fourcroydes, a plant native to Yucatan, Mexico.


A continuous length of yarn or cord of any desired length, in the form of a collapsible coil.

Ski Tow Rope – For Water; Usually a small diameter hollow braid polypropylene rope used for pulling water skiers behind motor boats. For Snow; Usually a three strand twisted rope of various synthetic fibers attached to a motor, this rope pulls skiers uphill.


To use a loop (bight) of rope instead of the end when closing a knot to make untying the knot easy.


A continuous strand of parallel overlapping natural fibers (manila, cotton, sisal, jute, etc.) ready for twisting.

Snatch Block:

A single sheave block with a hinged strap that can be opened and the bight of a line inserted.

Solid Braid:

A construction of 9, 12 or 18 strands of fiber, lock-stitched together. It has a smooth, round, firm contour which holds its shape well under pressure and load. It is excellent in pulleys and winches and whenever a firm round rope is needed. It is not as strong as other braids nor is it as spliceable.


In general, any mast, yard, pole or boom.

Specific Gravity:

– Ratio of the mass of a material to the mass of an equal volume of water.


A light, very large three cornered sail set flying forward of all fore stays. Used on racing yachts when running the wind.


The joining of two ends of yarn, strand or cordage by intertwining or inserting these ends into the body of the product. An eye splice may be formed by using a similar process to join one end into the body of the product.

Spring Lay:

A rope in which each strand consists partly if wire and partly of fiber. It is composed of six main strands laid around a fiber core. It will show fish hooks after it has been stressed.


A fiber that has been texturized by spinning before it is twisted into yarn, giving it a woolly texture, similar to cotton. It is common in nylon, polyester and Dacron™.

Standing Part:

The main part of the rope not in the knot itself, the rope not being tied is the standing part.

Standing Rigging – Rigging holding up the masts that is usually not adjusted while sailing.

Starter Cord:

A strong abrasion resistant braided cord usually of nylon; used for hand-wound gasoline engine starters and other utility purposes.

Stern Line:

Runs through the stern chock to control forward movement and assists the breast lines. Aft Spring.

Stopper Knot:

Used to stop the rope from pulling through a cleat, hole or pulley.


The largest individual element used in the final rope-making process and obtained by joining and twisting (or braiding) together several yarns or groups of yarns.


Natural fibers of cut lengths from filaments of man-made fibers. The staple length of natural fibers varies from less than 1″ for some cotton fibers to several feet for some hard fibers. Man-made fibers are cut to a definite length, usually about 1-1/2″ but occasionally down to 1″, so they can be processed on the cotton, woolen and worsted systems. The term staple (fiber) is used in the textile industry to distinguish natural or cut length man-made fibers from filament.

Stringing Line:

A line used for extending a wire or cable

Synthetic Fiber:

Any non-organic fiber used in rope or cordage manufacture.


Also called block and tackle. A means of gaining leverage by a line run through one or more blocks; usually two or more. The numbers of lines which support the load determine the mechanical advantage.


A coating of tar applied to various fibers, ropes, manila, nylon, etc. to limit absorbency.

Tensile Strength, Minimum:

A value based on a large number of breaking force tests representing a value that is two standard deviations below the mean. See: Breaking Strength, Minimum.


To process fibers in such a way as to ass texture and/or loft to the fiber.


Metal ring or eyelet around which a line is spliced. The line fits into the concave outside; the convex inside bears the strain and wear.


The end of a rib in a ship’s frame that projects above the deck and is used as a bollard.


Also called float line or cork line; a floating line on top of a net.


A force or a combination of forces that produces or tends to produce a twisting or rotating motion. When used in describing the performance or characteristic of yarn, the term torque refers to that character which tends to make it turn on itself as a result of twisting.


To pull; also, one or more barges or other floating vessels in charge of a self-propelled vessel which is transporting it or them.

Trot Line:

In fishing, a comparatively short set line used near shore or along streams.

Truck Rope:

Three strand polypropylene rope made to meet the standards established by the State of California, for holding down cargo or canvas in heavy truck transporting.


The number of turns about the axis applied to a fiber, yarn, strand or rope over a given length to combine the individual elements into a larger and stronger structure. The direction of rotation about the axis denoted as “S” (left hand) or “Z” (right hand) twist.

Twist, Balanced:

In a plied yarn or cord, an arrangement of twist which will not cause the yarn or cord to twist on itself when held in the form of an open loop.


The process of combining two or more parallel textile elements by controlling the lineal and rotational speeds of the material to produce a specific twist level.

U.V. Resistance:

Ability of a rope fiber to withstand decay due to the damaging effect of the ultraviolet rays of the sun.

– V –

Venetian Blind Cord:

A braided cord generally of nylon or cotton with various fiber cores.

– W –


A sturdy fabric woven in narrow widths for use where strength is required as for seat belts, head bands, etc.

Welt Cord:

A tape covered cord sewn into a seam as reinforcement or trimming.


A cord thread used to lash or bind the end of a rope to prevent unlaying.

Working End:

The end of a rope being worked into a knot.

Working Load:

Also known as working strength; the weight in pounds that is recommended for safe working conditions. It is applied to new rope in good condition with appropriate splices and only under normal service conditions. Where dynamic loading may occur, the recommended working load should be adjusted accordingly.

Working Load Limit:

The working load that must not be exceeded for a particular application as established by an engineer, supervisor, regulatory or standards setting agency.

Yacht Braid:

A braid on braid, double spliceable cord used as running rigging in sailing; usually polyester over polyester.


A generic term for a continuous strand of textile fibers, filaments or material in a form suitable for intertwining to form a textile structure via any one of a number of textile processes.

Yarn, Single:

The simplest textile structure available for processing into rope, twine or cordage.

Yarn, Plied:

A yarn formed by twisting together two or more single yarns in one operation in a direction opposite to the twist direction of the single yarns to produce a balanced structure.

Yoke Lifejacket:

Primarily designed for pack-carrying troops in an amphibious operation. It will keep an individual afloat even with a full pack of gear.

– Z –


Right handed twist; A twist that would be laid out by turning the yarn or rope in a clockwise direction.