- flan (n.)
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- "open tart," 1846, from French flan "custard tart, cheesecake," from Old French flaon "flat-cake, tart, flan" (12c.), from Medieval Latin flado (10c.), which probably is from Frankish *flado or another Germanic source (compare Old High German flado "offering cake," Middle High German vlade "a broad, thin cake," Dutch vla "baked custard"), from Proto-Germanic *flatho(n) "flat cake," probably from PIE root *plat- "to spread" (see plaice (n.)). Borrowed earlier as flawn (c. 1300), from Old French.