English
hot dog
From hot + dog, in reference to the supposed source of the meat, both in the senses of the food item (noun senses 1 and 2) and of a show-off (noun sense 3).
first attested First attested in 1884 (as stated in the etymology)
The story
From hot + dog, in reference to the supposed source of the meat, both in the senses of the food item (noun senses 1 and 2) and of a show-off (noun sense 3). First attested in 1884 in the Evansville (Indiana) Daily Courier.
Today it means
noun A sausage, typically a frankfurter.
Language periods are conventional ranges, not dates for this word.
Etymograph / hot dog