sesquipedalian

1. (of a word or words) Long; polysyllabic.Examples: "The most common use of "antidisestablishmentarianism" is as an example of a sesquipedalian word."; "He would use the simplest, plainest language, he said to himself over and over again; but it is not always easy to use simple, plain language,—by no means so easy as to mount on stilts, and to march along with sesquipedalian words, with pathos, spasms, and notes of interjection."; "Happy word hunting! You might bag a sesquipedalian trophy! (Look it up in the dictionary)."