Antidisestablishmentarianism: is a political philosophy that is opposed to the separation of church and state. The term originated in the context of the nineteenth century Church of England; antidisestablismentarians were opposed to proposals to remove its status as the state church of England. The term has largely fallen into disuse, although the issue itself is still current; witness recent disputes in the UK over the Act of Settlement.
It can be broken down as follows:
~ism .................. the philosophy of
~arian~ .............. those people who believe in
anti~ ................. opposition to
~dis~ ................ the removal of
~establishment~ .. the Church of England as the official state church
Antidisestablishmentarianism is often quoted as one of the longest English words that has an actual meaning.