polyvinylrododospagaspamomo!

or, how about nondiagonalizable! that word is so awesome to say lol

I'll probably get this one wrong... Pnumonoultramicroscopicsilicavolcanoconiosis
('n(y)ü-m&-(")nO-"&l-tr&-"mI-kr&-'skäp-ik-'sil-i-(")kO-väl-'kA-nO-"kO-nE-'O-s&s)