Jeans are the strong blue cotton trousers that almost everybody owns. Rivets at the pockets, and a seam you can see.
The cloth is denim, and the name comes from Genoa, where a similar fabric was made. They began as working clothes for miners in the nineteenth century and became the most worn garment on earth. The word is always plural, so you buy a pair of jeans. English keeps a family of related words, since denim, dungarees and jean jackets all belong to the same tradition.
1nounjeansHard-wearing trousers made of denim.
“He wore the same jeans all week.”
Latin
Genua
English, today
jeans
From Latin Genua. From Gene(s) (also spelled Jean(s)), an obsolete English name for the Italian city of Genoa. Compare Gênes. In the context of clothing, the term originally denoted a kind of coarse cotton (known more fully as Gene(s) fustian) that was associated with Genoa. It began to be used for trousers made of such cloth in the 19th century. At this point, the final -s was reanalysed as a plural ending.
Etymology from Wiktionary, CC BY-SA