What is the longest word in English?

Longest words in English?

 The Oxford University Press English Dictionary disqualifies the word nominated by The Reader's Digest with this withering put-down: 

“a factitious word alleged to mean 'a lung disease caused by inhalation of very fine silica dust usually found in volcanos' but occurring chiefly as an instance of a very long word”.
In its place, OUP nominates loccinaucinihilipilification (29 letters) as the longest genuine word, followed by antidisestablishmentarianism (28 letters). 

Julie flies a kite

Another rival for the 'longest word you ever heard' has 34 letters and features in a certain film. 

 
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