Outdoor clothing glossary

These terms are used specifically in the context of performance outdoor clothing, footwear and equipment such as sleeping bags, rucksacks and tents. Many of these terms are specific to the textile industry, while others may have very different meanings in other contexts. Some commonly used trade names are also included.

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2-layer	A laminated waterproof fabric consisting of outer woven face fabric and waterproof breathable barrier. A free hanging lining is often used to protect the barrier from wear and to give a more comfortable feel next to the skin, although this will add weight and bulk to the garment, so is not utilised in very lightweight designs.
3-layer	A laminated waterproof fabric consisting of outer woven face fabric, waterproof breathable barrier, and protective inner liner, bonded together in a 3-layer sandwich. Offers greater durability, lower bulk and quicker drying times than a 2-layer fabric + liner combination, but can feel less soft and supple.
Bartack	A type of high-density lock-stitch used to reinforce garment seams and joins likely to experience extra wear or stress.
Baselayer	Garment worn directly next-to-skin, designed to keep the skin dry and comfortable by transporting moisture away from the surface of the skin where it can evaporate or be transported into other clothing layers.
Bi-component	A woven or knitted fabric consisting of 2 different types of yarn. Typically used in baselayer garments to enhance wicking.
Box wall	A construction method used in down filled clothing and sleeping bags, which utilises individually constructed box shaped chambers to contain the down and therefore provide a uniform thickness of insulation within the garment or bag.
Breathability	The ability of a fabric (especially waterproof fabrics) to allow moisture vapour to pass through them. A breathable fabric will not stop you from sweating (sweating is a result of your body being too hot), but will reduce the amount of condensation that forms on the inside of the garment. The amount by which condensation is reduced, depends on several factors, including how breathable the fabric is, the climatic conditions, how much moisture vapour your body is producing.
Calandering	A process that compacts the fibres in a fabric to make it more wind resistant.
Cambrelle	Trade name. A synthetic fabric used as a lining in footwear, which is light, quick drying, and wicking.
Closed-cell foam	Expanded (filled with air bubbles) polymers used predominantly for sleeping mats. As the air bubbles within it’s structure are separate, the foam offers good insulation, is resistant to compression, and will not absorb water.
Coating	The cheapest way to make a fabric waterproof, by applying a liquid compound directly onto the back of the face fabric which then dries to form a waterproof and flexible barrier. Usually built up in a series of very thin layers.
Conduction	Heat lost from the body through direct contact with a cold object i.e. the ground.
Convection	Heat lost from the body through the warming of surrounding air which then moves away to be replaced by cold air. Also occurs in water.
CoolMax	Trade name. A type of polyester fibre with a specially shaped 4 channel cross-section, giving it a much larger surface area than normal cylindrical polyester fibres. This larger surface area promotes better movement of moisture (wicking). Used extensively in knitted form for base-layer garments.
Cordura	Trade name. A type of very abrasion resistant nylon fibre primarily used in woven fabric form to reinforce areas of high wear.
Core spun	A yarn consisting of 2 different types of fibre, with 1 type surrounding the other. A typical example would be cotton fibres surrounding a polyester fibre core.
Denier Gradient	A reference to using 2 different deniers of fibre in a fabric to enhance directional wicking. Used especially in baselayer fabrics where finer fibres on the outer surface effectively ‘pull’ moisture away from the inner surface of slightly courser fibres, because of their larger surface area.
Denier	A measure of fibre thickness. 1 denier means that 9,000 meters of yarn weighs one gram.
Dew point	The point at which moisture vapour condenses back into liquid form. This is not normally a concern because moisture vapour from the skin will have left the clothing system before this occurs. However, it is a big problem in very cold conditions when thick layers of insulating materials are worn, as this point can be within the clothing system or sleeping bag being used. Once the moisture has condensed, it freezes, drastically reducing the insulating ability of the garment or sleeping bag. The only effective way to prevent this is the use of vapour barriers.
Die-cut	Essentially using a ‘cookie cutter’ to very accurately cut pieces of fabric to specific shapes.
Downproof	Any fabric used to contain down must be very tightly woven (or coated) to prevent the feathers within the down from poking through.
Down	A very highly insulating material, as yet unbeaten by any synthetic material for warmth-to-weight ratio. Consists of fluffy down clusters and small feathers, most commonly from ducks or geese. The down clusters provide the best insulation, so the lower the percentage of feathers, the potentially higher the insulation ability of the down. Low priced duck down will have a down/feather ratio of about 60:40, while the highest quality Polish goose down will be about 96:4. Even products labelled ‘100% down’ will contain a percentage of feathers. The actual insulation ability of the down is expressed as it’s fill power.
DWR	Durable Water Repellent. A chemical finish applied to fabrics to resist water absorption/entry. Makes drops of water ‘bead up’ and roll off the fabric, rather than soak in. Applied to waterproof breathable fabrics to improve breathability in wet conditions, and reduce drying times.
Dyneema	Trade name. A type of polyester fibre with a very high tensile strength. Typically used to reinforce woven fabrics used in high wear areas. Can not be dyed, so is always white in colour.
Egyptian cotton	A high quality cotton with fibres much longer and stronger than normal cotton.
Encapsil	Trade name. A process that coats fibres with a waterproofing compound before they are woven, resulting in a highly water resistant fabric with no traditional coating that stiffens the fabric or can wear off prematurely.
EVA	A synthetic polymer, most commonly used in it’s expanded form for lightweight shock absorbing layers in footwear sole units (particularly running shoes).
Face fabric	The outer facing fabric of a coated or laminated textile.
Fibre	The thin strands that are bundled or twisted together to form a yarn.
Fill power	A measure of how much space (in cubic inches) a sample quantity of down will occupy. The higher the fill power, the more still air the down traps, and the greater the insulation it offers will be. American and European methods for measuring fill power do not give the same measurements (the American method gives a higher measure).
Flat-lock	A stitch used to join fabrics edge to edge. Results in a very low bulk and stretchy seam. Most commonly used on base layer and fleece garments.
Fleece	A knitted synthetic fabric which is brushed on both sides to give a soft ‘fluffy’ pile finish.
Full-grain Leather	Leather made from the full thickness of the animals hide.
Gore-Tex	Trade name. A durably waterproof and very highly breathable fabric manufactured in many different combinations of 2 and 3-layer lamination. The Gore-Tex membrane is manufactured from ePTFE, with an oiliophobic layer to prevent contamination of the membrane with oils (e.g. sunscreen). Gore-Tex XCR is the most recent version, offering 25% higher breathability compared to Classic Gore-Tex. Gore-Tex Pac-Lite is specifically designed for lightweight use, being used in a 2-layer form without a lining.
Hard shell	A fully waterproof, breathable outer garment. E.g. Gore-Tex.
Hollow fibre	Synthetic fibres with longitudinal voids which increase insulating ability. Typically polyester fibres used in the form of non-woven wadding in synthetic sleeping bags and clothing.
Hydrophilic coating	A breathable waterproof coating which allows moisture vapour to pass through by allowing molecules of water to be absorbed and then passing them along chemical chains.
Hydrophilic	Water loving.
Hydrophobic	Water hating. Synthetic fibres are inherently hydrophobic, which means that they do not absorb water into their structure. This means that they will dry very rapidly and are inherently shower resistant.
Hydrostatic head	A measurement of how waterproof a fabric is. It refers to the height of a water column the fabric can support before leaking.
Insensible perspiration	The continual loss of water vapour that occurs from the human skin (typically about 60ml per hour) when resting. The reason why condensation forms on the inside of impermeable (totally non-breathable) clothing even if not undertaking any exercise.
Intera	Trade name. A chemical treatment for synthetic fibres which makes their surface hydrophilic. This allows treated fibres to wick moisture over their surface but still dry rapidly, as moisture is not absorbed into their hydrophobic core.
Kevlar	Trade name. A type of very tough PA fibre, particularly resistant to cutting. Typically used to reinforce areas of high wear.
Knit	A fabric created by interlocking rows of yarn, typically giving the fabric extra bulk and stretch. Used extensively for baselayer, socks and fleece fabric.
Laminated	Bonded. Usually refers to the way the layers of a waterproof fabric are joined together.
Lapse rate	The amount by which air temperature drops with increased altitude.
Layering	The system of using various combinations of garments to maintain a comfortable body temperature. Usually consists of a next-to-skin baselayer, mid-layer and outer shell layer.
Lock-stitch	The most commonly used type of stitch for joining seams, etc on a garment.
Loft	The amount an insulating material (usually down) ‘fluffs up’, thereby trapping still air for insulation.
Lycra	Trade name. A type of synthetic fibre offering very good stretch and recovery.
Membrane	A microporus or hydrophilic polymer film, which is typically waterproof and breathable. Will always be laminated to a face fabric and/or lining fabric to ensure durability.
Merino wool	Provides good insulation, durability, odour resistance, and moisture absorption, but due to it’s very fine fibres feels very soft and does not have the itch of normal wool. Used extensively in socks and some brands of underwear.
Microclimate	Typically used to refer to the climate (i.e. temperature and humidity) within a clothing system, particularly next to the skin. Performance clothing systems attempt to keep this microclimate at a comfortable level, irrespective of environmental conditions and workload.
Microfibre	A very fine synthetic fibre, typically used to make soft, strong, quick drying and highly breathable fabrics. A microfibre has a thickness of less than 0.1 Denier.
Microporus	A material containing millions of very small holes. Microporus waterproof breathable fabrics work by having holes that are too small for liquid water to pass through, but are big enough to allow molecules of water vapour to pass through unrestricted.
Mid layer	Garment worn over a baselayer and under a shell layer to provide additional insulation (if required).
Moisture vapour	Moisture which has turned from a visible liquid into an invisible gas.
MVTR	Moisture vapour transmission rate. A measure of how much moisture vapour can pass through a fabric in a given time.
Napoleon pocket	A pocket located on the chest of a garment (usually an outer layer) accessed by reaching across the front of the body with the opposite hand. Most other types of pocket are easily obstructed by rucksack straps, climbing harness, and other climbing equipment (such as slings) carried over the should.
Neoprene	A synthetic polymer, most commonly used in it’s expanded form in wet suits, due to it’s good insulation and stretch properties.
Non-woven	A fabric in which it’s fibres are bonded together, rather than woven or knitted.
Nubuck	Full grain leather which has had it’s surface abraded to give a more uniform appearance.
Over-lock	A stitch used inside garments to prevent fabric edges from fraying.
PA	Polyamide. A tough and durable synthetic polymer, often referred to as ‘nylon’.
PE	Polyester. A synthetic polymer, of which many different types are available. Very widely used due to it’s low raw material cost.
Permethrin	A contact insecticide, predominantly used on mosquito nets to provide protection against being bitten through the net (when the net lies directly on the skin, for example). Also has insect repellent properties. It is recommended that regularly used nets are re-treated every 6 months.
Pertex	Trade name. A range of high quality, tightly woven nylon microfibre fabrics used extensively for sleeping bags, down clothing and lightweight windproof garments.
Pilling	The unsightly ‘bobbling’ that occurs on the surface of some fabrics such as fleece. Good quality fleece will be resistant to pilling.
Pit-zip	A zip opening located under the arm of a garment to allow for extra ventilation and cooling when needed.
Polartec	Trade name. A range of high quality fleece fabrics, available in many different weights and textures. The numbers that are sometimes used after the name (100, 200, 300) refer to the fabric weight (thickness). Polartec 100 is very versatile and used predominantly for shirts and lightweight garments. Polartec 200 is used predominantly for midweight jackets. Polartec 300 is predominantly used for heavy weight jackets, but is not so popular due to it’s bulk.
Polycotton	Fabrics which are a mixture of polyester and cotton fibres. The cotton content makes the fabric feel comfortable next to the skin, while the polyester content adds durability, crease resistance, and reduces drying times. Most commonly used for lightweight travel clothing such as trousers and shirts. However, woven synthetic fabrics with wicking treatments do now offer better performance.
Post Exercise Chill	The dramatic chilling effect that can occurs when exercise is stopped, but the skin and clothing remain wet with sweat. Performance base-layer garments limit this effect by wicking (moving) moisture off the skin and allowing it to evaporate away from the skin.
Powerstretch	Trade name. A single sided fleece fabric with excellent stretch and recovery. Used especially for close fitting garments.
PP	Polypropylene. A synthetic polymer, not widely used for fabrics.
PTFE	Polytetrafluor ethylene, also known by the trade name Teflon. The polymer used in it’s expanded form (ePTFE) to make Gore-Tex and Windstopper breathable membranes.
PU	Polyurethane. A synthetic polymer, most commonly used as a coating on waterproof fabrics, and in it’s expanded form for durable shock absorbing layers in footwear sole units.
Radiation	Heat lost from the body through direct energy loss to the surroundings. The type of heat loss which foil ‘space blankets’ attempt to reduce by reflecting heat back to the body.
RET	Resistance to Evaporative heat Transfer. A highly accurate but very expensive measurement of breathability. A low figure indicates a higher level of breathability. The combined breathability for multiple layers of fabric can easily be calculated by simply adding their RET values – something which is not possible with other methods of measuring breathability.
Reticulated foam	Expanded (filled with air bubbles) polymers, used predominantly for body-contact padding in rucksacks. The structure of the foam is very open, allowing air to circulate.
Rip-stop	A method of fabric weaving, easily identified by the square grid pattern it produces on the fabric surface. It allows fabrics to be made lighter, while maintaining a good level of tear strength, but does NOT make a fabric rip-proof.
Schoeller	Trade name. A range of high quality Swiss fabrics, typically combining high durability and stretch, used extensively in soft shell leg wear.
Seam sealed	Stitching a waterproof fabric punctures the waterproof barrier. Seam sealed garments (and other items like tent flysheets) have the stitching holes re-sealed with a heat and pressure bonded tape to eliminate leakage.
Shell layer	Outer garment worn over other clothing layers to provide protection from rain, snow and wind.
Silicone elastomer	Used predominantly for coating lightweight tent fabrics, due to it’s durability, UV resistance, and the increase in tear strength it gives to the fabric. Unfortunately it can not be factory seam sealed (the seam seal tape will not stick), so requires sealing by hand after purchase. Because it is non-breathable, it is rarely used for clothing.
Silk	A very comfortable and strong natural fibre, which dries quickly and remains comfortable next to the skin in both hot and cold conditions. Used mainly for ‘deluxe’ sleeping bag liners and underwear. However, it’s high cost and questionable ease of laundering make it unpopular.
Snow skirt	A snug fitting inner cuff around the body of a jacket designed to prevent powder snow from blowing up into the garment.
Soft shell	A garment that is not fully waterproof, but which provides much greater weather protection than a traditional fleece or baselayer. Typical properties include being windproof, quick drying, very highly breathable, and comfortable to wear for extended periods.
SPF	Sun Protection Factor. A measure of how much protection from damaging Ultra Violet sunlight an item of clothing provides. An SPF of 20, for example, allows the wearer to remain in the sun 20 times longer than if they were unprotected.
Spray rating	A British Standard for measuring the water repellence of a fabric.
Stitched-through	The most basic method used in down filled clothing and sleeping bags, which comprises of the inner and outer shell fabrics being directly stitched together to create chambers. This does, however, introduce non-insulating cold spots along the lines of stitching.
Suede	Leather with it’s most densely packed outer layer removed, leaving quite an open and rough textured structure (a by-product of producing fine glove leather). Typically used where waterproofing is not a priority.
Supplex	Trade name. A type of nylon made of very fine filaments, which offers a soft feel, good abrasion resistance, and quick drying times (compared to cotton).
Tactel	Trade name. A range of nylon fabrics, which offer a cotton feel, but the benefits of synthetics (quick drying, easy care, colour fastness, etc).
Temperature/humidity gradient	A reference to the difference in temperature and humidity required on opposite sides of a waterproof breathable fabric to facilitate moisture vapour transfer (breathing). Moisture vapour will naturally move from areas of higher humidity (higher concentration of water vapour) to areas of lower humidity. In the context of clothing, this will usually be away from the body (which is continually producing moisture vapour and heat) to the outside world (which is colder and less humid). As such, waterproof breathable fabrics work best as near to the skin as possible, and in cold dry environments (such as the polar regions). Hot and humid environments, on the other hand, can severally limit the functionality of this process, in some circumstances even allowing moisture vapour into the clothing system.
Vapour barrier	An impermeable (totally non-breathable) fabric or garment worn near to the skin in very cold or extreme cold conditions to prevent moisture vapour and liquid perspiration from wetting insulating materials were it can freeze. Most commonly used in boots (between liner and main socks) or sleeping bags (as a liner).
V-baffle	A construction method used in down filled clothing and sleeping bags, which utilises individually constructed V-shaped chambers.
Ventile	Trade name. A fabric developed during the second world war for fighter pilot immersion suits. Made from very tightly woven egyptian cotton, it is inherently windproof, very durable and breathable, is quiet, and feels comfortable next to the skin. In wet conditions, the cotton fibres absorb water and swell, blocking all the indices (gaps) in the fabric through which water can percolate. Usually used in a double layer to provide maximum weather protection. Excellent for polar conditions. Not popular for general outdoor use, due to it’s high cost.
Vibram	Trade name. Inventor of the original rubber walking boot sole (previously, leather or hob-nails were used). Now used by virtually all quality walking boot manufacturers. Offers a very good combination of grip and durability.
Wadding	A non-woven ‘mat’ of fibres. Typically used as the insulating layers in synthetic sleeping bags.
Warmth-to-weight	The amount of insulation a material provides for a given weight.
Warp knit	A method of knitting which produces a more stable, stronger fabric, compared to normal knitting.
Warp	Yarns running length-ways through a fabric.
Waterproof	For a fabric to be called waterproof, as opposed to just water or shower resistant, it must prevent water penetration even under pressure. The European Standard that a fabric must meet to be classed as waterproof is a minimum hydrostatic head of 1.5 meters. This is enough to keep out the heaviest possible rain, but is not enough to keep out water under pressure from rucksack straps or kneeling down. High quality waterproof fabrics will greatly exceed this standard (Gore-Tex has a hydrostatic head of 28 meters).
Weft	Yarns running width-ways through a fabric.
Wicking	The ability of a fabric to move liquid water through it’s structure. An essential function for any fabric worn next to the skin.
Windbloc	Trade name. A windproof fleece fabric utilising a windproof film typically laminated between 2 layers of lightweight fleece.
Windchill	The dramatic cooling effect the wind has on the human body. For example, an ambient temperature of 10ºC will feel more like -1ºC in a 40km/h wind. Even more noticeable if wet clothing is worn.
Windproof	For a fabric to be called windproof (as opposed to just wind resistant), it can allow no more than 11 litres of air to pass through per second per square meter, in a 50km/h wind. Wind protection is a vital function of outer garments in mild or cold weather conditions.
Windstopper	Trade Name. A windproof fleece fabric utilising a windproof and highly breathable ePTFE membrane, typically laminated between 2 layers of lightweight fleece, or a lightweight fleece outer and mesh inner.
Yarn	The bundles of fibre which are then knitted or woven to make a fabric.

This glossary is by no means complete! It will continue to expand and develop over time. Our aim with this glossary was to try to keep things as simple, straight forward, and relevant as possible. However, many of the subjects mentioned are potentially highly complex (e.g. methods of measuring breathability) and are best left to scientific publications and websites to examine further.

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Last updated December 31, 2002

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