Plural of hotdog: a sausage served in a long bread roll, or people who perform risky stunts to show off.
From German 'dachshund sausage' (named for the dachshund dog breed because of its elongated shape). Americans began calling it a 'hot dog' around 1900, possibly popularized at baseball games. The 'showing off' meaning came later from 'hotdog' as slang for an excellent performer.
Nobody knows for certain, but the hotdog might have been popularized by a vendor at the 1904 World's Fair in St. Louis who sold them faster than any other food—making it genuinely an all-American invention, even though the sausage is German!
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