A native or inhabitant of Berlin, Germany; also a type of German pastry filled with jam or jelly and covered with powdered sugar.
From Berlin plus the agent suffix -er, indicating a person from Berlin. The pastry meaning became associated with the city's culinary tradition.
In Berlin, they just call this pastry a 'Pfannkuchen,' but everywhere else in Germany calls it a 'Berliner'—one of those funny situations where the city's own name for something differs from what the rest of the country calls it.
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