DictionarydenimCotton fabric
noun

denim

DEN-im/ˈdenɪm/

Durable cotton cloth woven with diagonal ribs.

The folded denim shows its pale reverse and frayed cotton edge.

A folded length of sturdy indigo denim, with a turned-back corner exposing its pale reverse and a frayed edge revealing cotton threads, beside a small folded pair of jeans that establishes its familiar use.
Etymology

The pieces mean “from Nîmes,” identifying the town in the phrase “serge from Nîmes.” Originally naming a kind of serge, denim later came to mean the coarse twilled cotton cloth used for jeans.

In context

Lukas Schanderl1:47
And what I love about this outfit is how casual but still refined it is because of the tie. He's wearing denim on denim. So he has a pair of jeans and then also a denim shirt underneath.
5 Stylish Ways to Wear a Seersucker Jacket Everyday

More examples

  • The denim softens after a few washes.
  • He wears a denim jacket on cool evenings.
  • Dark denim pairs well with a white shirt.

Similar words

twill
Twill describes a diagonal weave, not specifically sturdy cotton.
canvas
Canvas is usually plain-woven rather than diagonally ribbed.