5 words for denim beginners
When you first enter the world of denim. The 5 basic terms you should learn first are non-selvedge, selvedge, indigo, fade and weight.
This is a beginners guide for you to quickly understand what denim is about.
For pro content click the links below to dig deeper in each terminology.
Advanced denim dictionary
What is denim?
Denim is a twill fabric known for its characteristic diagonal ribbing and blue color. The denim twill is also known as the 3x1 weave construction where three warp (lengthwise) threads go over one weft (crosswise) thread, creating the diagonal pattern that contributes to its durability and comfort.
Denim is usually made of cotton or cotton-blend. Jeans are pants made with denim fabric.
The Origin of Denim
The term "denim" derives from the French phrase "serge de Nimes", meaning "serge from Nimes" (serge is a type of sturdy fabric). Over time, the shortened word de Nîmes evolved into the word “denim” when the fabric reached England and America and was adopted for workwear.
What is selvedge denim?
The term comes from combining “self” and “edge,” referring to fabric that finishes itself at the edge as it comes off the loom. It is easily recognized by its tightly woven, self-finished edge. Authentic selvedge denim is widely regarded as the highest-quality denim in the world.
The Perfect Imperfection
Woven on vintage shuttle looms, selvedge denim carries a natural irregularity that is inherent to the shuttle loom weaving process. These subtle imperfections create the distinctive character exclusive to denim. Such textures cannot be replicated by modern machinery, which makes selvedge denim especially rare.
Selvedge ID
Selvedge fabrics are often distinguished by a colored line — known as the selvedge ID — running along the edge of the fabric. This line is typically woven in red, blue, or white.
Shuttle Loom
A shuttle loom is a traditional weaving machine that creates fabric by passing a boat-shaped tool, called a shuttle, back and forth between the vertical warp threads to carry the horizontal weft thread. Before the invention of the projectile loom, traditional denim was made only on shuttle looms.
As shuttle looms were no longer in production around 50 years ago, most operating shuttle looms today are antiques that age more than 50 years old. Once the machine breaks there’re no new parts for replacement. Making it a rare craft that still carries on in a few places in the world.
What is non-selvedge denim
In contrast to selvedge denim, non-selvedge denim lacks a self-finished edge and is woven on projectile looms. The result is a fabric that looks and feels more modern and uniform. Non-selvedge denim is ideal for mass-produced commercial items that prioritize consistency over ruggedness and artisanal quality. Probably 99% of the jeans on the market today are made of non-selvedge fabric.
Projectile Loom (Wide loom)
Projectile looms became widely adopted after the 1950s and can be woven with 10–13 times the efficiency compared to shuttle looms. These machines use small, bullet-like projectiles to carry the weft thread through the warp threads, allowing for much higher speed and efficiency than traditional shuttle looms.
What is indigo?
Indigo is a deep blue dye extracted from the leaves of certain plants. One of the most common sources is the indigofera plant.
The word "indigo" comes from the Latin word indicum, meaning "Indian", as the naturally based dye was originally exported to Europe from India.
For consistency and scalability, most of the indigo dye used in denim yarns today is synthetic.
Indigo Rope Dyeing Technique
Rope-dyed indigo is a dyeing process where multiple cotton yarn strands are bundled into a "rope" and then repeatedly dipped into indigo dye baths, followed by exposure to air to oxidized indigo dye to bond to the fibers. This method is primarily used for denim, producing ring-dyed yarn in which the indigo coats only the outer layers while leaving the cotton core white. The result is yarn that fades gradually with wear, developing the unique and highly prized “fade” patterns that denim is known for.
Why does denim fade?
The most unique thing about denim is that it is made of indigo rope dyed yarns, which are destined to fade over time. The indigo coating on the cotton yarns gradually chips away through movement and interaction with the environment. This process slowly reveals the white cotton core, transforming the fabric from dark blue to lighter shades over time.
“Denim is the only fabric in the world that will constantly rejuvenate itself.” Quote what Maria from Nudie Jeans said
There’re plenty of reasons to fall in love with denim. Our favorite one is that it will evolve through time and wear, creating a unique story with the environment and the story of the wearer.
What is ‘ounce’ in denim?
Denim is measured by how many ounces(oz) are in a square yard of fabric.
Usually lightweight denim is 7-10oz, standard-weight is 10-14oz, mid-weight denim is 14-16oz, over 16oz is considered heavyweight. There’re Japanese brands that specialize in making 21oz + denim, which would be referred to as super heavyweight denim.
Denim Weight Explained
The most common weight of jeans on the market range from 9oz to 14oz. Uniqlo, GAP, Levis or any big names that you can name usually falls between this range. Think of a 20oz denim that weighs twice as heavy as a pair of 9oz light weight Uniqlo jeans. It’s a pretty straightforward concept.
What is the ideal denim weight?
There are many factors that can affect how a denim feels to your body. Generally the most comfortable jeans are under 13oz within the standard range. Commercial brands often prioritize comfort for mass consumers, so their jeans rarely exceed this weight due to cost considerations and hand feel.
A few critical factors to keep in mind are composition, durability, and appearance. Lightweight denim with stretch tends to lose its shape over time, while heavier fabrics generally provide greater durability and rougher texture. The same goes for fiber composition — the higher the cotton composition, the stronger the fabric; the more stretch or synthetic fibers, the less durable and softer the denim becomes.
Among premium denim brands, fabrics weighing between 12 and 14oz are the most common. Many of the original jeans from the 20th century also fell within this range, a tradition that continues today. Mid-weight denim not only offers more authentic character than lightweight denim, but also provides comfort while maintaining good durability.
Perhaps you’d be interested in learning more about good jeans, in the next 11 minute article we’ll talk about the 5 key words you need to know before shopping for good jeans.