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fem. proper name, variation of Madeline. The kind of small, rich confection is attested from 1845, said in OED to be named for Madeleine Paulmier, 19c. French pastry cook; any use with a sense of "small thing that evokes powerful nostalgia" is due to Proust (1922).
Paris church designed by Pierre-Alexandre Vignon in 1806. The Madeleine, in the form of a Roman temple surrounded by a Corinthian colonnade, reflects the taste for classical art and architecture that predominated in France during the Empire phase of the Neoclassical movement
delicate, scallop-shaped French tea cake often served with fruit or sherbet. In its preparation, flour, eggs, and sugar are beaten with a large proportion of butter, incorporating as much air as possible; then grated lemon rind and vanilla extract, and sometimes rum, are added. After baking in the customary 12-shell tin, the pastry is served plain or dusted with confectioner's sugar.