(used in the plural) close-fitting trousers of heavy denim for manual work or casual wear
"The workers arrived at the construction site wearing their faded blue jeans and hard hats."
A textile often made of cotton with a distinct diagonal pattern.
"The jeans were crafted from durable denim featuring its characteristic diagonal weave."
In plain English: Denim is the sturdy cotton fabric used to make jeans and jackets.
"She wore blue denim jeans to the casual dinner party."
Usage: Denim refers specifically to the durable twill fabric used in jeans and jackets, not the garments themselves. While people often use it as an adjective before clothing items like "denim jacket," remember that its core meaning describes the material's distinctive weave rather than any specific style of apparel.
The word denim comes from the French phrase de Nîmes, meaning "from Nîmes." It refers to the fabric that was originally produced in the town of Nîmes before traveling into English usage.