This word is too cool for school

Sesquipedalian

Main Entry: ses·qui·pe·da·lian
Pronunciation: "ses-kw&-p&-'dAl-y&n
Function: adjective
Etymology: Latin sesquipedalis, literally, a foot and a half long, from sesqui- + ped-, pes foot -- more at FOOT
1 : having many syllables : LONG "sesquipedalian terms"
2 : given to or characterized by the use of long words "a sesquipedalian television commentator"

Makes diphthong seem less cool, even though it still is.