Floccinaucinihipilification, meaning “the categorizing of something as worthless or trivial,” is a 29-letter, 12-syllable word that dates back to 1741. Until 1982, floccinaucinihipilification was the longest word in the Oxford English Dictionary. While it contains nine i’s, it is the longest word devoid of any e.
Pneumonoultramicroscopicsilicovolcanoconiosis This hippopotomonstrosesquipedalian word is the longest enshrined in Merriam Webster’s Third New International Dictionary and, since 1982, the longest in the Oxford English Dictionary. The word describes a miners’ disease caused by inhaling too much quartz or silicate dust. Among its 45 letters and 19 syllables occur nine o’s, surely the record for a letter most repeated within a single word; six c’s; and but one e.
Supercalifragilisticexpialidocious is a thirty-four letter word invented for the film version of Mary Poppins (1964) that has become our best known really, really big word. Etymo_logically, this is not entirely a nonsense word. Stitched together, supercalifragilisticexpialidocious means “atoning for extreme and delicate beauty [while being] highly educable.”