wiener n.

capital of Austria, Latin Vindobona, from Gaulish vindo- "white," from Celtic *vindo- (source also of Old Irish find, Welsh gwyn "white;" see Gwendolyn) + bona "foundation, fort." The "white" might be a reference to the river flowing through it. Related: Viennese.

German sausage, 1855, from German Wurst, from Old High German wurst "sausage," probably etymologically "mixture," from Proto-Germanic *wursti-, from PIE *wers- (1) "to confuse, mix up" (see war (n.)).

"frankfurter," 1906, with slang sense of "penis" following soon after, from German wienerwurst "Vienna sausage" (see wiener). Meaning "ineffectual person, effeminate young man" is slang from 1963; pejorative sense via penis shape, or perhaps from weenie in the sense of "small" (see wee).