What is the longest word in the english dictionary?

You're unlikely to come across these words in genuine use: they're generally just provided as answers to questions about the longest words in the English language. In terms of sheer size, however, the longest word to be found in Britain is the Welsh place name Llanfairpwllgwyngyllgogerychwyrndrobwllllantysiliogogogoch. read more

Pneumonoultramicroscopicsilicovolcanoconiosis (/ ˌ nj uː m ə n oʊ ˌ ʌ l t r ə ˌ m aɪ k r ə ˈ s k ɒ p ɪ k ˌ s ɪ l ɪ k oʊ v ɒ l ˌ k eɪ n oʊ ˌ k oʊ n i ˈ oʊ s ɪ s / ( listen)) is a word invented by the president of the National Puzzlers' League as a synonym for the disease known as silicosis. read more

The longest word in any of the major English language dictionaries is pneumonoultramicroscopicsilicovolcanoconiosis, a word that refers to a lung disease contracted from the inhalation of very fine silica particles, specifically from a volcano; medically, it is the same as silicosis. read more