What Is Denim, Really?

Denim isn’t a color, and it’s not a specific type of cotton—it’s a weave. A twill weave, to be exact. More specifically, it’s a warp-faced twill, which means the warp yarns (the ones running vertically on the loom) are more dominant on the surface than the weft (horizontal) yarns.

This is what gives denim its signature diagonal ribbing on the face of the fabric and a smoother underside. You’ve probably seen this if you’ve ever cuffed your jeans—the inside is usually lighter. That’s because classic denim uses indigo-dyed warp threads and undyed or white weft threads, giving it that blue-outside/white-inside effect.

A Little History

The name denim comes from serge de Nîmes, a sturdy fabric made in Nîmes, France. Over time, the phrase was shortened to “denim.” Originally, it was used for durable workwear, and it’s stuck around for exactly that reason—it’s tough, it ages well, and it’s a bit of a chameleon in terms of style.

So What Makes Denim…Denim?

Here are the basics:

• Weave  Always a twill (usually 3x1 right-hand twill).
• Fiber  Typically 100% cotton, but nowadays often blended with stretch fibers like elastane.
• Color  Traditionally, indigo-dyed warp with undyed weft, but modern denim comes in every color.
• Weight  Varies from lightweight chambray-style to heavy-duty raw denim.
  
  

Chambray vs Denim

A common confusion: chambray looks similar but is plain-woven (not twill). So while both can be made from cotton and dyed with indigo, the weave pattern and feel are different. Chambray is softer and lighter, while denim has that tougher, more textured finish.

 

See what we mean —> Verdalina Denim Collection