The word "wiener" is a direct borrowing from the German "Wienerwurst," meaning "Vienna sausage." It is a demonym, derived from "Wien," the German name for Vienna, Austria, where this style of sausage originated. The term entered English in the late 19th century, initially referring specifically to the smoked, thin sausage from Vienna. Through common usage, especially in North America, "wiener" became a general synonym for a frankfurter or hot dog, and later, through humorous slang, acquired a secondary, anatomical meaning.

The word is a loanword from German, derived from the city name "Wien" (Vienna). It functions as a whole unit in English.