Denier /ˈdɛnjər/ or den is a unit of measure for the linear mass density of fibers. It is defined as the mass in grams per 9000 meters. The denier is based on a natural standard—i.e., a single strand of silk is approximately one denier. A 9000-meter strand of silk weighs about one gram. In other words, it gives scale to the weight and thickness of the hosiery products. The lower the denier, the thinner is the product. Stockings and tights with a higher denier are more durable.

+ bare legs effect –sheer tights/ stockings- ultra-thin tights or stockings that give the effect of bare legs (normally less than 20 DEN)

+ semi-opaque and opaque stockings or tights made of a heavier yarn (usually 40 one or more) that make them thicker and less transparent appearance.

Spandex-is an elastic synthetic fiber which is better known under the trade name of Lycra (trademark of DuPont) elastin fibers can be stretched from four to seven times their length, returning to their original length.

Phlebology – department of medicine dealing with the diagnosis and diseases of the veins.

Gusset-usually diamond-shaped or triangular insert in the seam between the legs in pantyhose gives greater durability, comfort, and hygiene.

Lycra-is a registered trademark of Invista (DuPont). It stands for a flexible synthetic fabric with an elastic stretching capacity of up to 600% and back to the original size. Clothes made of Lycra are very strong and flexible, giving you comfort, great fit, and freedom of movement.

Lycra3D-is the result of the development of new technologies that change the way knitwear look and behave. The 3D Lycra means Lycra yarn is knitted in different directions, giving an extremely smooth and comfortable texture, stretchability in all directions, and an excellent fit to the skin. Products with Lycra 3D give exceptional comfort. The unique softness and silkiness are apparent the moment the product is taken out of the pack. 

Microfiber– a type of nylon yarn, made of a number of thin strands or fibers which are bonded together into a single fiber. This way the yarn becomes very flexible, durable, resistant to wrinkling, has more volume. Tiny threads or filaments can move back and forth and maneuver within the fibers of the fabric to allow better alignment and stretch freely while maintaining its volume.

Nylon is a polyamide yarn. It is an artificial yarn, made from basic ingredients derived from petrochemicals. Nylon has a natural shine, but can be given a darker look.

Polyamide-chemical name of some artificial fibers. An alternative name is nylon.  The name polyamide is sometimes used instead of the name of nylon in content declarations, appearing on packaging.

Hold-ups-stockings that cling to the leg by elastic straps sewn lace (reinforced with silicone), so it is not necessary to use a garter belt.

Seam-in the ’50s of the XXth century stockings were knitted flat and then the two sides were sewn together forming the seam.  These Fully Fashioned Stockings (FFS) are now quite rare.

+ Flat seam hosiery with flat seams are more comfortable because they do not leave marks on the body.  A special technique is used to achieve flat seams, and the products with flat seams are considered of higher quality.

+ Seamless stockings or tights-uniform stockings or tights that are knitted in one operation on circular machines (one continuous operation) so that the seam is not required.

Compression stockings, tights, knee-highs (Light, Medium, Strong compression grad) – Hosiery, specially woven to achieve a different level of pressure on the ankles, knees, and thighs. Pressure gradually decreases from the ankle to the thigh to ensure proper blood circulation, reduces ankle swelling, varicose veins, or fatigue in the legs due to prolonged standing.

+ Light gradual pressure (mmHg 3-10) is for people who do not have any health problems or problems with their feet but want to reduce fatigue and make you feel comfortable during prolonged standing.

+ Average gradual pressure (mmHg 10-15) is for women whose legs feel constantly tired, or those who are prone (genetically or because of their profession) to have varicose veins and puffy ankles.

+ Strong gradual pressure (mmHg 15-22) is designed for people with common health problems such as varicose veins or poor circulation. Products with this level of compression will improve the condition and alleviate discomfort and pain.

+ MmHg-Symbol millimeters of mercury – a unit of pressure, used in medicine to measure blood pressure, defined as the pressure exerted by a column of mercury one millimeter high, under the force of gravity. Also used in graduated compression to determine the amount of pressure that the hosiery product has on the circumference of the leg.

Reinforced heel-heel area reinforced with thicker and heavier (see Denier) yarn.

+ Cuban heel– a type of heel on a fully fashioned stocking, whereby the reinforced part is squared off above the back of the ankle, rather than tapering to a point.

+ French heel– type of heel fully fashioned stockings, where reinforced part tapers to a point. This helps to emphasize the length and shape of the legs.

Reinforced toes – Hosiery with thickened parts around the toes, made of thicker and heavier yarn (often to avoid ripping speed which occurs most often around the toes).

Reinforced Top– Tights with reinforced panties made of thicker (higher den) yarn to provide shaping support. They are specially knitted with stronger yarn to visually correct certain areas: slim the tummy, smoothen the body lines around the hips or push up the bottom.