supercalifragilisticexpialidocious

The story

Possibly a fanciful elaboration of super (“better than average, wonderful”) (compare super- (prefix denoting something superior in status or title, in potency or power, etc.)), with -istic (“suffix meaning ‘of or relating to’ forming adjectives from nouns”) and -ious (suffix forming adjectives from nouns, denoting the presence of a quality in any degree (typically an abundance)). Various explanations of the other elements of the word have been suggested, but none of them are supported by convincing evidence. One by the American linguist Richard Lederer (born 1938) in his book Crazy English (1989) is super- + cali- (a variant of calli- (prefix meaning ‘beautiful’)) + fragilistic- (from fragile (“delicate”)) + expiali- (from expiate (“to atone or make reparation for”)) + docious (“amenable to order, docile”), suggesting that the word means “atoning for extreme and delicate beauty [while being] highly educable”. For the -docious ending, compare braggadocious (“exhibiting braggadocio, characterized by empty boasts”), first attested in American English in 1853. The word was popularized by its use in the song “Supercalifragilisticexpialidocious” from the 1964 film Mary Poppins, written by the American songwriters Robert B. Sherman (1925–2012) and Richard M. Sherman (1928–2024); they wrote in 1998: “When we were little boys in the mid-1930s, we went to a summer camp in the Adirondack Mountains, where we were introduced to a very long word that had been passed down in many variations through many generations of kids. […] The word as we first heard it was super-cadja-flawjalistic-espealedojus.”