This word is really good for practicing the vowel sound in English! Because there is so many vowel sounds in here!
An-ti-dis-e-stab-blish-ment-air-ria-nism (Antidisestablishmentarianism)
Meaning :
Being opposed to the separation of church and state.
It's a word that nowadays we don't quite use it at all. But in the past it may be a little bit more common.