A person who arrives, especially someone who has recently come to a place or achieved success.
From French 'arriver' (to arrive) plus the agent suffix '-er' creating a noun for one who performs the action. It entered English from French in the 18th-19th centuries.
An 'arriver' isn't just someone who showed up—it often means someone who worked hard to 'arrive' at success or status, which is why 'nouveau arriver' (new arrival) can be slightly jealous-sounding in English.
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