A person who is devoted to or preoccupied with following the latest fashions and trends.
From 'fashion' plus the agent suffix '-ist' (one who practices or is devoted to something). This word is less common than 'fashionista' but has the same formation pattern as 'journalist' or 'pianist'.
This is an older, more formal way to describe what we now call a 'fashionista'—showing how different generations create new terms for the same idea!
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