We have already had an absolutely huge debate on this recently and I think the number of posts went into the 100s. I don't think we want to start it all over again so I am cutting this thread off here, sorry.
Please run a quick search of the forum and you will find the existing thread.
floccinaucinihilipilification is longer than antidisastablishmentarianism by one letter but is not as well known. Some people also say that pneumonoultramicroscopicsilicovolcanoconiosis is the longest word. I'm not sure what is right
PNEUMONOULTRAMICROSCOPICSILICOVOLCANOCONIOSIS (45 letters; a lung disease caused by breathing in certain particles) is the longest word in any English-language dictionary. (It is also spelled -koniosis.)
How can pneumonoultramicroscopicsilicovolcanoconiosis be a single word? Isn't it just silicovolcanoconiosis of a pneumonoultramicroscopic nature? Doesn't that mean that all microscopic specimens can be microscopicspecimens, or microscopic doses microscopicdoses, etc.?
When are you allowed to form a long word from an adjective and noun and when not?