windfall
コンビニの店員が間違って違う種類の宝くじを売ってしまいましたが、それが大当たりでした。
New Hampshire man wins $2.1 million Megabucks lottery after convenience store clerk sells him the wrong ticket
On a whim, Bennett, 48, stopped into the Circle K convenience store in his hometown of Hillsborough, N. H., and told the clerk he wanted one ticket each for the Lucky for Life and Megabucks games.
But as fate would have it, the clerk, 42-year-old Nicki Gee, misunderstood Bennett.
“The clerk sold him two Tri State Megabucks Plus tickets," Maura McCann, New Hampshire Lottery director of marketing, told WMUR news. "He never got his Lucky For Life ticket."
Opting for a one-time lump payment of $1.3 million, the Bennetts say that they will use their sudden windfall to pay down student loan debt for two of their children, send their third child to college, remodel their kitchen, and maybe purchase a few extra Christmas presents.
windfallは「意外な授かりもの、たなぼた〈主に遺産〉;宝くじの賞金」「（収穫前に風で落ちた）果物；リンゴ」（『ジーニアス英和辞典 第４版』大修館）と定義されています。windとfallというよく見る英語が組み合わさった単語だったので、すぐに語源が気になりました。OnlineEtymologyDictionaryには、"mid-15c., from wind (n.) + fall (n.1). Originally literal, in reference to wood or fruit blown down by the wind, and thus free to all. Figurative sense of "unexpected acquisition" is recorded from 1540s."との記述がありました。また、イラストで解説されているサイトもありました。http://thealoof.com/origin-of-the-word-windfall/
嘘か本当かはわかりませんが、あのニュートンの有名な逸話の発見も、windfall（棚からぼたもち）と言えるのでしょうか。（Astroriver）
