fashion
n. C / Un. the popular style of clothes, hair, or behavior at a certain time. You use this when talking about what is currently 'in' or trendy.
n. a prevailing custom or style of dress, etiquette, or socializing. Often used to describe the industry or the collective trends of a specific era.
Jeans are always in fashion.
The fashion of the 1970s included bright colors and wide trousers.
Fast fashion has fundamentally altered the retail landscape by shortening the time between a design's appearance on the runway and its availability to the general public.
Inherited from Middle English facioun, from Anglo-Norman fechoun (compare Jersey Norman faichon), variant of Old French faceon, fazon, façon (“fashion, form, make, outward appearance”), from Latin factiō (“a making”), from faciō (“do, make”); see fact. Doublet of faction.
Uncountable when referring to the general concept or industry; countable when referring to a specific style or manner.
He dresses in a modern fashionHe dresses in a modern styleWhile 'fashion' can mean 'manner', learners often use it where 'style' is more natural for describing personal clothing choices.